NEW JERSEY
STUDENT LEARNING STANDARDS
FOR
Mathematics | Grade 3
New Jersey Student Learning Standards for Mathematics
2
Mathematics | Grade 3
In Grade 3, instructional time should focus on four critical areas: (1) developing
understanding of multiplication and division and strategies for multiplication and division
within 100; (2) developing understanding of fractions, especially unit fractions (fractions
with numerator 1); (3) developing understanding of the structure of rectangular arrays
and of area; and (4) describing and analyzing two-dimensional shapes.
(1) Students develop an understanding of the meanings of multiplication and division of
whole numbers through activities and problems involving equal-sized groups, arrays, and
area models; multiplication is finding an unknown product, and division is finding an
unknown factor in these situations. For equal-sized group situations, division can require
finding the unknown number of groups or the unknown group size. Students use
properties of operations to calculate products of whole numbers, using increasingly
sophisticated strategies based on these properties to solve multiplication and division
problems involving single-digit factors. By comparing a variety of solution strategies,
students learn the relationship between multiplication and division.
(2) Students develop an understanding of fractions, beginning with unit fractions.
Students view fractions in general as being built out of unit fractions, and they use
fractions along with visual fraction models to represent parts of a whole. Students
understand that the size of a fractional part is relative to the size of the whole. For
example, 1/2 of the paint in a small bucket could be less paint than 1/3 of the paint in a
larger bucket, but 1/3 of a ribbon is longer than 1/5 of the same ribbon because when
the ribbon is divided into 3 equal parts, the parts are longer than when the ribbon is
divided into 5 equal parts. Students are able to use fractions to represent numbers equal
to, less than, and greater than one. They solve problems that involve comparing fractions
by using visual fraction models and strategies based on noticing equal numerators or
denominators.
(3) Students recognize area as an attribute of two-dimensional regions. They measure the
area of a shape by finding the total number of same size units of area required to cover
the shape without gaps or overlaps, a square with sides of unit length being the standard
unit for measuring area. Students understand that rectangular arrays can be decomposed
into identical rows or into identical columns. By decomposing rectangles into rectangular
arrays of squares, students connect area to multiplication, and justify using multiplication
to determine the area of a rectangle.
(4) Students describe, analyze, and compare properties of two-dimensional shapes. They
compare and classify shapes by their sides and angles, and connect these with definitions
of shapes. Students also relate their fraction work to geometry by expressing the area of
part of a shape as a unit fraction of the whole.
New Jersey Student Learning Standards for Mathematics
3
Mathematical Practices
1. Make sense of problems and persevere in
solving them.
2. Reason abstractly and quantitatively.
3. Construct viable arguments and critique the
reasoning of others.
4. Model with mathematics.
5. Use appropriate tools strategically.
6. Attend to precision.
7. Look for and make use of structure.
8. Look for and express regularity in repeated
reasoning
Grade 3 Overview
Operations and Algebraic Thinking
• Represent and solve problems involving
multiplication and division.
• Understand properties of multiplication and
the relationship between multiplication and
division.
• Multiply and divide within 100.
• Solve problems involving the four
operations, and identify and explain patterns
in arithmetic.
Number and Operations in Base Ten
• Use place value understanding and
properties of operations to perform multi-
digit arithmetic.
Number and Operations—Fractions
• Develop understanding of fractions as numbers.
Measurement and Data
• Solve problems involving measurement and estimation of intervals of
time, liquid volumes, and masses of objects.
• Represent and interpret data.
• Geometric measurement: understand concepts of area and relate area to
multiplication and to addition.
• Geometric measurement: recognize perimeter as an attribute of plane
figures and distinguish between linear and area measures.
Geometry
• Reason with shapes and their attributes.
New Jersey Student Learning Standards for Mathematics
4
Operations and Algebraic Thinking 3.OA
A. Represent and solve problems involving multiplication and division.
1. Interpret products of whole numbers, e.g., interpret 5 × 7 as the total number of objects in 5
groups of 7 objects each. For example, describe and/or represent a context in which a total
number of objects can be expressed as 5 × 7.
2. Interpret whole-number quotients of whole numbers, e.g., interpret 56 ÷ 8 as the number of
objects in each share when 56 objects are partitioned equally into 8 shares, or as a number of
shares when 56 objects are partitioned into equal shares of 8 objects each. For example,
describe and/or represent a context in which a number of shares or a number of groups can
be expressed as 56 ÷ 8.
3. Use multiplication and division within 100 to solve word problems in situations involving
equal groups, arrays, and measurement quantities, e.g., by using drawings and equations
with a symbol for the unknown number to represent the problem.
1
4. Determine the unknown whole number in a multiplication or division equation relating three
whole numbers. For example, determine the unknown number that makes the equation true
in each of the equations 8 × ? = 48, 5 =
�
÷ 3, 6 × 6 = ?.
B. Understand properties of multiplication and the relationship between multiplication and
division.
5. Apply properties of operations as strategies to multiply and divide.
2
Examples: If 6 × 4 = 24 is
known, then 4 × 6 = 24 is also known. (Commutative property of multiplication.) 3 × 5 × 2 can
be found by 3 × 5 = 15, then 15 × 2 = 30, or by 5 × 2 = 10, then 3 × 10 = 30. (Associative
property of multiplication.) Knowing that 8 × 5 = 40 and 8 × 2 = 16, one can find 8 × 7 as 8 × (5
+ 2) = (8 × 5) + (8 × 2) = 40 + 16 = 56. (Distributive property.)
6. Understand division as an unknown-factor problem. For example, find 32 ÷ 8 by finding the
number that makes 32 when multiplied by 8.
C. Multiply and divide within 100.
7. Fluently multiply and divide within 100, using strategies such as the relationship between
multiplication and division (e.g., knowing that 8 × 5 = 40, one knows 40 ÷ 5 = 8) or properties
of operations. By the end of Grade 3, know from memory all products of two one-digit
numbers.
D. Solve problems involving the four operations, and identify and explain patterns in
arithmetic.
8. Solve two-step word problems using the four operations. Represent these problems using
equations with a letter standing for the unknown quantity. Assess the reasonableness of
answers using mental computation and estimation strategies including rounding.
3
9. Identify arithmetic patterns (including patterns in the addition table or multiplication table),
and explain them using properties of operations. For example, observe that 4 times a number
is always even, and explain why 4 times a number can be decomposed into two equal
addends.
1
See Glossary, Table 2.
2
Students need not use formal terms for these properties.
3
This standard is limited to problems posed with whole numbers and having whole number answers; students should know how to
perform operations in the conventional order when there are no parentheses to specify a particular order (Order of Operations).
New Jersey Student Learning Standards for Mathematics
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Number and Operations in Base Ten 3.NBT
A. Use place value understanding and properties of operations to perform multi-digit
arithmetic.
4
1. Use place value understanding to round whole numbers to the nearest 10 or 100.
2. Fluently add and subtract within 1000 using strategies and algorithms based on place value,
properties of operations, and/or the relationship between addition and subtraction.
3. Multiply one-digit whole numbers by multiples of 10 in the range 10–90 (e.g., 9 × 80, 5 × 60)
using strategies based on place value and properties of operations.
Number and Operations—Fractions
5
3.NF
A. Develop understanding of fractions as numbers.
1. Understand a fraction 1/b as the quantity formed by 1 part when a whole is partitioned into
b equal parts; understand a fraction a/b as the quantity formed by a parts of size 1/b.
2. Understand a fraction as a number on the number line; represent fractions on a number line
diagram.
a. Represent a fraction 1/b on a number line diagram by defining the interval from 0 to 1 as
the whole and partitioning it into b equal parts. Recognize that each part has size 1/b and
that the endpoint of the part based at 0 locates the number 1/b on the number line.
b. Represent a fraction a/b on a number line diagram by marking off a lengths 1/b from 0.
Recognize that the resulting interval has size a/b and that its endpoint locates the number
a/b on the number line.
3. Explain equivalence of fractions in special cases, and compare fractions by reasoning about
their size.
a. Understand two fractions as equivalent (equal) if they are the same size, or the same point
on a number line.
b. Recognize and generate simple equivalent fractions, e.g., 1/2 = 2/4, 4/6 = 2/3). Explain why
the fractions are equivalent, e.g., by using a visual fraction model.
c. Express whole numbers as fractions, and recognize fractions that are equivalent to whole
numbers. Examples: Express 3 in the form 3 = 3/1; recognize that 6/1 = 6; locate 4/4 and 1
at the same point of a number line diagram.
d. Compare two fractions with the same numerator or the same denominator by reasoning
about their size. Recognize that comparisons are valid only when the two fractions refer to
the same whole. Record the results of comparisons with the symbols >, =, or <, and justify
the conclusions, e.g., by using a visual fraction model.
Measurement and Data 3.MD
A. Solve problems involving measurement and estimation of intervals of time, liquid volumes,
and masses of objects.
1. Tell and write time to the nearest minute and measure time intervals in minutes. Solve word
problems involving addition and subtraction of time intervals in minutes, e.g., by
representing the problem on a number line diagram.
4
A range of algorithms may be used.
5
Grade 3 expectations in this domain are limited to fractions with denominators 2, 3, 4, 6, and 8.
New Jersey Student Learning Standards for Mathematics
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2. Measure and estimate liquid volumes and masses of objects using standard units of grams
(g), kilograms (kg), and liters (l).
6
Add, subtract, multiply, or divide to solve one-step word
problems involving masses or volumes that are given in the same units, e.g., by using
drawings (such as a beaker with a measurement scale) to represent the problem.
7
B. Represent and interpret data.
3. Draw a scaled picture graph and a scaled bar graph to represent a data set with several
categories. Solve one- and two-step “how many more” and “how many less” problems using
information presented in scaled bar graphs. For example, draw a bar graph in which each
square in the bar graph might represent 5 pets.
4. Generate measurement data by measuring lengths using rulers marked with halves and
fourths of an inch. Show the data by making a line plot, where the horizontal scale is marked
off in appropriate units— whole numbers, halves, or quarters.
C. Geometric measurement: understand concepts of area and relate area to multiplication and
to addition.
5. Recognize area as an attribute of plane figures and understand concepts of area
measurement.
a. A square with side length 1 unit, called “a unit square,” is said to have “one square unit” of
area, and can be used to measure area.
b. A plane figure which can be covered without gaps or overlaps by n unit squares is said to
have an area of n square units.
6. Measure areas by counting unit squares (square cm, square m, square in, square ft, and non-
standard units).
7. Relate area to the operations of multiplication and addition.
a. Find the area of a rectangle with whole-number side lengths by tiling it, and show that the
area is the same as would be found by multiplying the side lengths.
b. Multiply side lengths to find areas of rectangles with whole number side lengths in the
context of solving real world and mathematical problems, and represent whole-number
products as rectangular areas in mathematical reasoning.
c. Use tiling to show in a concrete case that the area of a rectangle with whole-number side
lengths a and b + c is the sum of a × b and a × c. Use area models to represent the
distributive property in mathematical reasoning.
d. Recognize area as additive. Find areas of rectilinear figures by decomposing them into non-
overlapping rectangles and adding the areas of the non-overlapping parts, applying this
technique to solve real world problems.
D. Geometric measurement: recognize perimeter as an attribute of plane figures and
distinguish between linear and area measures.
8. Solve real world and mathematical problems involving perimeters of polygons, including
finding the perimeter given the side lengths, finding an unknown side length, and exhibiting
rectangles with the same perimeter and different areas or with the same area and different
perimeters.
6
Excludes compound units such as cm3 and finding the geometric volume of a container.
7
Excludes multiplicative comparison problems (problems involving notions of “times as much”; see Glossary, Table 2).
New Jersey Student Learning Standards for Mathematics
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Geometry 3.G
A. Reason with shapes and their attributes.
1. Understand that shapes in different categories (e.g., rhombuses, rectangles, and others) may
share attributes (e.g., having four sides), and that the shared attributes can define a larger
category (e.g., quadrilaterals). Recognize rhombuses, rectangles, and squares as examples of
quadrilaterals, and draw examples of quadrilaterals that do not belong to any of these
subcategories.
2. Partition shapes into parts with equal areas. Express the area of each part as a unit fraction
of the whole. For example, partition a shape into 4 parts with equal area, and describe the
area of each part as 1/4 of the area of the shape.
New Jersey Student Learning Standards for Mathematics
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Mathematics | Standards for Mathematical Practice
The Standards for Mathematical Practice describe varieties of expertise that mathematics
educators at all levels should seek to develop in their students. These practices rest on important
“processes and proficiencies” with longstanding importance in mathematics education. The first
of these are the NCTM process standards of problem solving, reasoning and proof,
communication, representation, and connections. The second are the strands of mathematical
proficiency specified in the National Research Council’s report Adding It Up: adaptive reasoning,
strategic competence, conceptual understanding (comprehension of mathematical concepts,
operations and relations), procedural fluency (skill in carrying out procedures flexibly, accurately,
efficiently and appropriately), and productive disposition (habitual inclination to see mathematics
as sensible, useful, and worthwhile, coupled with a belief in diligence and one’s own efficacy).
1 Make sense of problems and persevere in solving them.
Mathematically proficient students start by explaining to themselves the meaning of a problem
and looking for entry points to its solution. They analyze givens, constraints, relationships, and
goals. They make conjectures about the form and meaning of the solution and plan a solution
pathway rather than simply jumping into a solution attempt. They consider analogous problems,
and try special cases and simpler forms of the original problem in order to gain insight into its
solution. They monitor and evaluate their progress and change course if necessary. Older
students might, depending on the context of the problem, transform algebraic expressions or
change the viewing window on their graphing calculator to get the information they need.
Mathematically proficient students can explain correspondences between equations, verbal
descriptions, tables, and graphs or draw diagrams of important features and relationships, graph
data, and search for regularity or trends. Younger students might rely on using concrete objects
or pictures to help conceptualize and solve a problem. Mathematically proficient students check
their answers to problems using a different method, and they continually ask themselves, “Does
this make sense?” They can understand the approaches of others to solving complex problems
and identify correspondences between different approaches.
2 Reason abstractly and quantitatively.
Mathematically proficient students make sense of quantities and their relationships in problem
situations. They bring two complementary abilities to bear on problems involving quantitative
relationships: the ability to decontextualize—to abstract a given situation and represent it
symbolically and manipulate the representing symbols as if they have a life of their own, without
necessarily attending to their referents—and the ability to contextualize, to pause as needed
during the manipulation process in order to probe into the referents for the symbols involved.
Quantitative reasoning entails habits of creating a coherent representation of the problem at
hand; considering the units involved; attending to the meaning of quantities, not just how to
compute them; and knowing and flexibly using different properties of operations and objects.
3 Construct viable arguments and critique the reasoning of others.
Mathematically proficient students understand and use stated assumptions, definitions, and
previously established results in constructing arguments. They make conjectures and build a
logical progression of statements to explore the truth of their conjectures. They are able to
analyze situations by breaking them into cases, and can recognize and use counterexamples.
They justify their conclusions, communicate them to others, and respond to the arguments of
others. They reason inductively about data, making plausible arguments that take into account
New Jersey Student Learning Standards for Mathematics
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the context from which the data arose. Mathematically proficient students are also able to
compare the effectiveness of two plausible arguments, distinguish correct logic or reasoning
from that which is flawed, and—if there is a flaw in an argument—explain what it is. Elementary
students can construct arguments using concrete referents such as objects, drawings, diagrams,
and actions. Such arguments can make sense and be correct, even though they are not
generalized or made formal until later grades. Later, students learn to determine domains to
which an argument applies. Students at all grades can listen or read the arguments of others,
decide whether they make sense, and ask useful questions to clarify or improve the arguments.
4 Model with mathematics.
Mathematically proficient students can apply the mathematics they know to solve problems
arising in everyday life, society, and the workplace. In early grades, this might be as simple as
writing an addition equation to describe a situation. In middle grades, a student might apply
proportional reasoning to plan a school event or analyze a problem in the community. By high
school, a student might use geometry to solve a design problem or use a function to describe
how one quantity of interest depends on another. Mathematically proficient students who can
apply what they know are comfortable making assumptions and approximations to simplify a
complicated situation, realizing that these may need revision later. They are able to identify
important quantities in a practical situation and map their relationships using such tools as
diagrams, two-way tables, graphs, flowcharts and formulas. They can analyze those relationships
mathematically to draw conclusions. They routinely interpret their mathematical results in the
context of the situation and reflect on whether the results make sense, possibly improving the
model if it has not served its purpose.
5 Use appropriate tools strategically.
Mathematically proficient students consider the available tools when solving a mathematical
problem. These tools might include pencil and paper, concrete models, a ruler, a protractor, a
calculator, a spreadsheet, a computer algebra system, a statistical package, or dynamic geometry
software. Proficient students are sufficiently familiar with tools appropriate for their grade or
course to make sound decisions about when each of these tools might be helpful, recognizing
both the insight to be gained and their limitations. For example, mathematically proficient high
school students analyze graphs of functions and solutions generated using a graphing calculator.
They detect possible errors by strategically using estimation and other mathematical knowledge.
When making mathematical models, they know that technology can enable them to visualize the
results of varying assumptions, explore consequences, and compare predictions with data.
Mathematically proficient students at various grade levels are able to identify relevant external
mathematical resources, such as digital content located on a website, and use them to pose or
solve problems. They are able to use technological tools to explore and deepen their
understanding of concepts.
6 Attend to precision.
Mathematically proficient students try to communicate precisely to others. They try to use clear
definitions in discussion with others and in their own reasoning. They state the meaning of the
symbols they choose, including using the equal sign consistently and appropriately. They are
careful about specifying units of measure, and labeling axes to clarify the correspondence with
quantities in a problem. They calculate accurately and efficiently, express numerical answers with
a degree of precision appropriate for the problem context. In the elementary grades, students
give carefully formulated explanations to each other. By the time they reach high school they
have learned to examine claims and make explicit use of definitions.
New Jersey Student Learning Standards for Mathematics
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7 Look for and make use of structure.
Mathematically proficient students look closely to discern a pattern or structure. Young students,
for example, might notice that three and seven more is the same amount as seven and three
more, or they may sort a collection of shapes according to how many sides the shapes have.
Later, students will see 7 × 8 equals the well remembered 7 × 5 + 7 × 3, in preparation for
learning about the distributive property. In the expression x
2
+ 9x + 14, older students can see the
14 as 2 × 7 and the 9 as 2 + 7. They recognize the significance of an existing line in a geometric
figure and can use the strategy of drawing an auxiliary line for solving problems. They also can
step back for an overview and shift perspective. They can see complicated things, such as some
algebraic expressions, as single objects or as being composed of several objects. For example,
they can see 5 – 3(x – y)
2
as 5 minus a positive number times a square and use that to realize that
its value cannot be more than 5 for any real numbers x and y.
8 Look for and express regularity in repeated reasoning.
Mathematically proficient students notice if calculations are repeated, and look both for general
methods and for shortcuts. Upper elementary students might notice when dividing 25 by 11 that
they are repeating the same calculations over and over again, and conclude they have a
repeating decimal. By paying attention to the calculation of slope as they repeatedly check
whether points are on the line through (1, 2) with slope 3, middle school students might abstract
the equation (y – 2)/(x – 1) = 3. Noticing the regularity in the way terms cancel when expanding (x
– 1)(x + 1), (x – 1)(x
2
+ x + 1), and (x – 1)(x
3
+ x
2
+ x + 1) might lead them to the general formula for
the sum of a geometric series. As they work to solve a problem, mathematically proficient
students maintain oversight of the process, while attending to the details. They continually
evaluate the reasonableness of their intermediate results.
New Jersey Student Learning Standards for Mathematics
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Connecting the Standards for Mathematical Practice to the Standards for
Mathematical Content
The Standards for Mathematical Practice describe ways in which developing student practitioners
of the discipline of mathematics increasingly ought to engage with the subject matter as they
grow in mathematical maturity and expertise throughout the elementary, middle and high school
years. Designers of curricula, assessments, and professional development should all attend to the
need to connect the mathematical practices to mathematical content in mathematics instruction.
The Standards for Mathematical Content are a balanced combination of procedure and
understanding. Expectations that begin with the word “understand” are often especially good
opportunities to connect the practices to the content. Students who lack understanding of a topic
may rely on procedures too heavily. Without a flexible base from which to work, they may be less
likely to consider analogous problems, represent problems coherently, justify conclusions, apply
the mathematics to practical situations, use technology mindfully to work with the mathematics,
explain the mathematics accurately to other students, step back for an overview, or deviate from
a known procedure to find a shortcut. In short, a lack of understanding effectively prevents a
student from engaging in the mathematical practices.
In this respect, those content standards, which set an expectation of understanding, are potential
“points of intersection” between the Standards for Mathematical Content and the Standards for
Mathematical Practice. These points of intersection are intended to be weighted toward central
and generative concepts in the school mathematics curriculum that most merit the time,
resources, innovative energies, and focus necessary to qualitatively improve the curriculum,
instruction, assessment, professional development, and student achievement in mathematics.
New Jersey Student Learning Standards for Mathematics
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Glossary
Addition and subtraction within 5, 10, 20, 100, or 1000. Addition or subtraction of two whole numbers
with whole number answers, and with sum or minuend in the range 0-5, 0-10, 0-20, or 0-100, respectively.
Example: 8 + 2 = 10 is an addition within 10, 14 – 5 = 9 is a subtraction within 20, and 55 – 18 = 37 is a
subtraction within 100.
Additive inverses. Two numbers whose sum is 0 are additive inverses of one another. Example: 3/4 and –
3/4 are additive inverses of one another because 3/4 + (– 3/4) = (– 3/4) + 3/4 = 0.
Associative property of addition. See Table 3 in this Glossary.
Associative property of multiplication. See Table 3 in this Glossary.
Bivariate data. Pairs of linked numerical observations. Example: a list of heights and weights for each
player on a football team.
Box plot. A method of visually displaying a distribution of data values by using the median, quartiles, and
extremes of the data set. A box shows the middle
50% of the data.
1
Commutative property. See Table 3 in this Glossary.
Complex fraction. A fraction A/B where A and/or B are fractions (B nonzero).
Computation algorithm. A set of predefined steps applicable to a class of problems that gives the correct
result in every case when the steps are carried out correctly. See also: computation strategy.
Computation strategy. Purposeful manipulations that may be chosen for specific problems, may not have a
fixed order, and may be aimed at converting one problem into another. See also: computation algorithm.
Congruent. Two plane or solid figures are congruent if one can be obtained from the other by rigid motion
(a sequence of rotations, reflections, and translations).
Counting on. A strategy for finding the number of objects in a group without having to count every
member of the group. For example, if a stack of books is known to have 8 books and 3 more books are
added to the top, it is not necessary to count the stack all over again. One can find the total by counting
on—pointing to the top book and saying “eight,” following this with “nine, ten, eleven. There are eleven
books now.”
Dot plot. See: line plot.
Dilation. A transformation that moves each point along the ray through the point emanating from a fixed
center, and multiplies distances from the center by a common scale factor.
Expanded form. A multi-digit number is expressed in expanded form when it is written as a sum of single-
digit multiples of powers of ten. For example, 643 = 600 + 40 + 3.
Expected value. For a random variable, the weighted average of its possible values, with weights given by
their respective probabilities.
First quartile. For a data set with median M, the first quartile is the median of the data values less than M.
Example: For the data set {1, 3, 6, 7, 10, 12, 14, 15, 22, 120}, the first quartile is 6.
2
See also: median, third
quartile, interquartile range.
Fraction. A number expressible in the form a/b where a is a whole number and b is a positive whole
number. (The word fraction in these standards always refers to a non-negative number.) See also: rational
number.
Identity property of 0. See Table 3 in this Glossary.
Independently combined probability models. Two probability models are said to be combined
independently if the probability of each ordered pair in the combined model equals the product of the
original probabilities of the two individual outcomes in the ordered pair.
1
Adapted from Wisconsin Department of Public Instruction, http://dpi.wi.gov/standards/mathglos.html , accessed March 2, 2010.
2
Many different methods for computing quartiles are in use. The method defined here is sometimes called the Moore and McCabe
method. See Langford, E., “Quartiles in Elementary Statistics,” Journal of Statistics Education Volume 14, Number 3 (2006).
New Jersey Student Learning Standards for Mathematics
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Integer. A number expressible in the form a or –a for some whole number a.
Interquartile Range. A measure of variation in a set of numerical data, the interquartile range is the
distance between the first and third quartiles of the data set. Example: For the data set {1, 3, 6, 7, 10, 12,
14, 15, 22, 120}, the interquartile range is 15 – 6 = 9. See also: first quartile, third quartile.
Line plot. A method of visually displaying a distribution of data values where each data value is shown as a
dot or mark above a number line. Also known as a dot plot.
3
Mean. A measure of center in a set of numerical data, computed by adding the values in a list and then
dividing by the number of values in the list.
4
Example: For the data set {1, 3, 6, 7, 10, 12, 14, 15, 22, 120},
the mean is 21.
Mean absolute deviation. A measure of variation in a set of numerical data, computed by adding the
distances between each data value and the mean, then dividing by the number of data values. Example:
For the data set {2, 3, 6, 7, 10, 12, 14, 15, 22, 120}, the mean absolute deviation is 20.
Median. A measure of center in a set of numerical data. The median of a list of values is the value
appearing at the center of a sorted version of the list—or the mean of the two central values, if the list
contains an even number of values. Example: For the data set {2, 3, 6, 7, 10, 12, 14, 15, 22, 90}, the median
is 11.
Midline. In the graph of a trigonometric function, the horizontal line halfway between its maximum and
minimum values.
Multiplication and division within 100. Multiplication or division of two whole numbers with whole
number answers, and with product or dividend in the range 0-100. Example: 72 ÷ 8 = 9.
Multiplicative inverses. Two numbers whose product is 1 are multiplicative inverses of one another.
Example: 3/4 and 4/3 are multiplicative inverses of one another because 3/4 × 4/3 = 4/3 × 3/4 = 1.
Number line diagram. A diagram of the number line used to represent numbers and support reasoning
about them. In a number line diagram for measurement quantities, the interval from 0 to 1 on the diagram
represents the unit of measure for the quantity.
Percent rate of change. A rate of change expressed as a percent. Example: if a population grows from 50 to
55 in a year, it grows by 5/50 = 10% per year.
Probability distribution. The set of possible values of a random variable with a probability assigned to
each.
Properties of operations. See Table 3 in this Glossary.
Properties of equality. See Table 4 in this Glossary.
Properties of inequality. See Table 5 in this Glossary.
Properties of operations. See Table 3 in this Glossary.
Probability. A number between 0 and 1 used to quantify likelihood for processes that have uncertain
outcomes (such as tossing a coin, selecting a person at random from a group of people, tossing a ball at a
target, or testing for a medical condition).
Probability model. A probability model is used to assign probabilities to outcomes of a chance process by
examining the nature of the process. The set of all outcomes is called the sample space, and their
probabilities sum to 1. See also: uniform probability model.
Random variable. An assignment of a numerical value to each outcome in a sample space.
Rational expression. A quotient of two polynomials with a non-zero denominator.
Rational number. A number expressible in the form a/b or – a/b for some fraction a/b. The rational
numbers include the integers.
Rectilinear figure. A polygon all angles of which are right angles.
Rigid motion. A transformation of points in space consisting of a sequence of one or more translations,
reflections, and/or rotations. Rigid motions are here assumed to preserve distances and angle measures.
3
Adapted from Wisconsin Department of Public Instruction, op. cit.
4
To be more precise, this defines the arithmetic mean.
New Jersey Student Learning Standards for Mathematics
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Repeating decimal. The decimal form of a rational number. See also: terminating decimal.
Sample space. In a probability model for a random process, a list of the individual outcomes that are to be
considered.
Scatter plot. A graph in the coordinate plane representing a set of bivariate data. For example, the heights
and weights of a group of people could be displayed on a scatter plot.
5
Similarity transformation. A rigid motion followed by a dilation
Tape diagram. A drawing that looks like a segment of tape, used to illustrate number relationships. Also
known as a strip diagram, bar model, fraction strip, or length model.
Terminating decimal. A decimal is called terminating if its repeating digit is 0.
Third quartile. For a data set with median M, the third quartile is the median of the data values greater
than M. Example: For the data set {2, 3, 6, 7, 10, 12, 14, 15, 22, 120}, the third quartile is 15. See also:
median, first quartile, interquartile range.
Transitivity principle for indirect measurement. If the length of object A is greater than the length of
object B, and the length of object B is greater than the length of object C, then the length of object A is
greater than the length of object C. This principle applies to measurement of other quantities as well.
Uniform probability model. A probability model which assigns equal probability to all outcomes. See also:
probability model.
Vector. A quantity with magnitude and direction in the plane or in space, defined by an ordered pair or
triple of real numbers.
Visual fraction model. A tape diagram, number line diagram, or area model.
Whole numbers. The numbers 0, 1, 2, 3, ….
5
Adapted from Wisconsin Department of Public Instruction, op. cit.
New Jersey Student Learning Standards for Mathematics
15
Table 1. Common addition and subtraction situations.
6
Result Unknown Change Unknown Start Unknown
Add to
Two bunnies sat on the grass.
Three more bunnies hopped
there. How many bunnies are
on the grass now?
2 + 3 = ?
Two bunnies were sitting on
the grass. Some more bunnies
hopped there. Then there
were five bunnies. How many
bunnies hopped over to the
first two?
2 + ? = 5
Some bunnies were sitting on
the grass. Three more bunnies
hopped there. Then there
were five bunnies. How many
bunnies were on the grass
before?
? + 3 = 5
Take from
Five apples were on the table. I
ate two apples. How many
apples are on the table now?
5 – 2 = ?
Five apples were on the table.
I ate some apples. Then there
were three apples. How many
apples did I eat?
5 – ? = 3
Some apples were on the
table. I ate two apples. Then
there were three apples. How
many apples were on the
table before?
? – 2 = 3
Total Unknown Addend Unknown Both Addends Unknown
1
Put Together/
Take Apart
2
Three red apples and two green
apples are on the table. How
many apples are on the table?
3 + 2 = ?
Five apples are on the table.
Three are red and the rest are
green. How many apples are
green?
3 + ? = 5, 5 – 3 = ?
Grandma has five flowers.
How many can she put in her
red vase and how many in her
blue vase?
5 = 0 + 5, 5 = 5 + 0
5 = 1 + 4, 5 = 4 + 1
5 = 2 + 3, 5 = 3 + 2
Difference Unknown Bigger Unknown Smaller Unknown
Compare
3
(“How many more?” version):
Lucy has two apples. Julie has
five apples. How many more
apples does Julie have than
Lucy?
(“How many fewer?” version):
Lucy has two apples. Julie has
five apples. How many fewer
apples does Lucy have than
Julie?
2 + ? = 5, 5 – 2 = ?
(Version with “more”):
Julie has three more apples
than Lucy. Lucy has two
apples. How many apples
does Julie have?
(Version with “fewer”):
Lucy has 3 fewer apples than
Julie. Lucy has two apples.
How many apples does Julie
have?
2 + 3 = ?, 3 + 2 = ?
(Version with “more”):
Julie has three more apples
than Lucy. Julie has five
apples. How many apples
does Lucy have?
(Version with “fewer”):
Lucy has 3 fewer apples than
Julie. Julie has five apples.
How many apples does Lucy
have?
5 – 3 = ?, ? + 3 = 5
1
These take apart situations can be used to show all the decompositions of a given number. The associated equations, which have the total on the left of the
equal sign, help children understand that the = sign does not always mean makes or results in but always does mean is the same number as.
2
Either addend can be unknown, so there are three variations of these problem situations. Both Addends Unknown is a productive extension of this basic
situation, especially for small numbers less than or equal to 10.
3
For the Bigger Unknown or Smaller Unknown situations, one version directs the correct operation (the version using more for the bigger unknown and using
less for the smaller unknown). The other versions are more difficult.
6
Adapted from Box 2-4 of National Research Council (2009, op. cit., pp. 32, 33).
New Jersey Student Learning Standards for Mathematics
16
Table 2. Common multiplication and division situations.
7
Unknown Product
Group Size Unknown
(“How many in each group?”
Division)
Number of Groups Unknown
(“How many groups?”
Division)
3 x 6 = ?
3 x ? = 18, and 18 ÷ 3 = ? ? x 6 = 18, and 18 ÷ 6 = ?
Equal Groups
There are 3 bags with 6 plums
in each bag. How many plums
are there in all?
Measurement example. You
need 3 lengths of string, each
6 inches long. How much string
will you need altogether?
If 18 plums are shared equally
into 3 bags, then how many
plums will be in each bag?
Measurement example. You
have 18 inches of string, which
you will cut into 3 equal pieces.
How long will each piece of
string be?
If 18 plums are to be packed 6
to a bag, then how many bags
are needed?
Measurement example. You
have 18 inches of string, which
you will cut into pieces that are
6 inches long. How many pieces
of string will you have?
Arrays,
4
Area
5
There are 3 rows of apples
with 6 apples in each row. How
many apples are there?
Area example. What is the area
of a 3 cm by 6 cm rectangle?
If 18 apples are arranged into 3
equal rows, how many apples
will be in each row?
Area example. A rectangle has
area 18 square centimeters. If
one side is 3 cm long, how long
is a side next to it?
If 18 apples are arranged into
equal rows of 6 apples, how
many rows will there be?
Area example. A rectangle has
area 18 square centimeters. If
one side is 6 cm long, how long
is a side next to it?
Compare
A blue hat costs $6. A red hat costs
3 times as much as the
blue hat. How much does the
red hat cost?
Measurement example. A
rubber band is 6 cm long. How
long will the rubber band be
when it is stretched to be 3
times as long?
A red hat costs $18 and that is
3 times as much as a blue hat
costs. How much does a blue
hat cost?
Measurement example. A
rubber band is stretched to be
18 cm long and that is 3 times
as long as it was at first. How
long was the rubber band at
first?
A red hat costs $18 and a blue
hat costs $6. How many times
as much does the red hat cost
as the blue hat?
Measurement example. A
rubber band was 6 cm long at
first. Now it is stretched to be
18 cm long. How many times as
long is the rubber band now as
it was at first?
General
a × b = ? a × ? = p, and p ÷ a = ? ? × b = p, and p ÷ b = ?
4
The language in the array examples shows the easiest form of array problems. A harder form is to use the terms rows and columns: The apples in
the grocery window are in 3 rows and 6 columns. How many apples are in there? Both forms are valuable.
5
Area involves arrays of squares that have been pushed together so that there are no gaps or overlaps, so array problems include these especially
important measurement situations.
7
The first examples in each cell are examples of discrete things. These are easier for students and should be given
before the measurement examples.
New Jersey Student Learning Standards for Mathematics
17
Table 3. The properties of operations. Here a, b and c stand for arbitrary numbers in a given number
system. The properties of operations apply to the rational number system, the real number system, and the
complex number system.
Associative property of addition (a + b) + c = a + (b + c)
Commutative property of addition a + b = b + a
Additive identity property of 0 a + 0 = 0 + a = a
Existence of additive inverses For every a there exists –a so that a + (–a) = (–a) + a = 0.
Associative property of multiplication (a x b) x c = a x (b x c)
Commutative property of multiplication a x b = b x a
Multiplicative identity property of 1 a x 1 = 1 x a = a
Existence of multiplicative inverses For every a ≠ 0 there exists 1/a so that a x 1/a = 1/a x a = 1.
Distributive property of multiplication over addition a x (b + c) = a x b + a x c
Table 4. The properties of equality. Here a, b and c stand for arbitrary numbers in the rational, real, or
complex number systems.
Reflexive property of equality
a = a
Symmetric property of equality
If a = b, then b = a.
Transitive property of equality
If a = b and b = c, then a = c.
Addition property of equality
If a = b, then a + c = b + c.
Subtraction property of equality
If a = b, then a – c = b – c.
Multiplication property of equality
If a = b, then a x c = b x c.
Division property of equality
If a = b and c ≠ 0, then a ÷c = b
÷
c.
Substitution property of equality
If a = b, then b may be substituted for a
in any expression containing a.
Table 5. The properties of inequality. Here a, b and c stand for arbitrary numbers in the rational or real
number systems.
Exactly one of the following is true: a < b, a = b, a > b.
If a > b and b > c then a > c.
If a > b, then b < a.
If a > b, then –a < –b.
If a > b, then a ± c > b ± c.
If a > b and c > 0, then a x c > b x c.
If a > b and c < 0, then a x c < b x c.
If a > b and c > 0, then a ÷c > b ÷ c.
If a > b and c < 0, then a ÷c < b ÷ c.
