
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.
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,
Common Core State Standards for MAT HEMAT ICS
standards for mathematical practice,
communicate them to others, and respond to the arguments of others. They reason
inductively about data, making plausible arguments that take into account 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, twoway 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.
Common Core State Standards for MAT HEMAT ICS
standards for mathematical practice 
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 x 8equals the
well remembered 7 × 5 + 7 × 3, in preparation for learning about the distributive
property. In the expression x2 + 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)(x2 + x + 1), and (x – 1)(x3 + x2 + 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.