Grade 1 Math Colorado standards Standards

Geometry

Measurement & Data

Operations & Algebraic Thinking

Number & Operations in Base Ten

Standards for Mathematical Practice

Reason with shapes and their attributes.

Geometry: Reason with shapes and their attributes.

Distinguish between defining attributes (e.g., triangles are closed and three-sided) versus non-defining attributes (e.g., color, orientation, overall size); build and draw shapes to possess defining attributes.

Distinguish between defining attributes (e.g., the number of sides and angles) versus non-defining attributes (e.g., color, orientation, overall size) or circles, squares, rectangles, or triangles.

Compose two-dimensional shapes (rectangles, squares, trapezoids, triangles, half-circles, and quarter-circles) or three-dimensional shapes (cubes, right rectangular prisms, right circular cones, and right circular cylinders) to create a composite shape, and compose new shapes from the composite shape. (Students do not need to learn formal names, such as "right rectangular prisms.")

Compose two or more two-dimensional shapes (rectangles, squares, triangles, and half circles) to create a composite shape.

For example, join two half circles to make a circle.

Partition circles and rectangles into two and four equal shares, describe the shares using the words halves, fourths, and quarters, and use the phrases half of, fourth of, and quarter of. Describe the whole as two of, or four of the shares. Understand for these examples that decomposing into more equal shares creates smaller shares.

Partition circles and rectangles into two equal shares and demonstrate an understanding of “half.”

Measure lengths indirectly and by iterating length units.

Measurement & Data: Measure lengths indirectly and by iterating length units.

Order three objects by length; compare the lengths of two objects indirectly by using a third object.

Order three objects by length using direct comparisons.

Express the length of an object as a whole number of length units, by laying multiple copies of a shorter object (the length unit) end to end; understand that the length measurement of an object is the number of same-size length units that span it with no gaps or overlaps. Limit to contexts where the object being measured is spanned by a whole number of length units with no gaps or overlaps.

Express the length of an object as a whole number of length units, by laying multiple copies of a shorter object (the length unit) end to end.

Limit contexts where the object being measured is spanned by a whole number of fewer than 5 length units with no gaps or overlaps.

Examples: “The paper is three pencils long,” “The book is 5 blocks wide.”

Tell and write time.

Measurement & Data: Tell and write time.

Tell and write time in hours and half-hours using analog and digital clocks.

Demonstrate an understanding of the terms morning, afternoon, day, and night.

Represent and interpret data.

Measurement & Data: Represent and interpret data.

Organize, represent, and interpret data with up to three categories; ask and answer questions about the total number of data points, how many in each category, and how many more or less are in one category than in another.

Organize data into two categories by sorting.

Answer questions about the number of data points in each category (lmit category counts to be less than or equal to 10). (EE:1.MD.C.4)

Extend the counting sequence.

Number & Operations in Base Ten: Extend the counting sequence.

Count to 120, starting at any number less than 120. In this range, read and write numerals and represent a number of objects with a written numeral.

Count to up to at least 20, starting at any number less than 20.

In this range, identify numerals and represent (by writing, matching, or otherwise indicating) a number of objects with a written numeral.

Understand place value.

Number & Operations in Base Ten: Understand place value.

Understand that the two digits of a two-digit number represent amounts of tens and ones. Understand the following as special cases:

Understand that the two digits of the numbers 10 through 20 represent amounts of tens and ones.

10 can be thought of as a bundle of ten ones — called a "ten."

Understand the following as special cases: 10 ca be thought of a bundle of ten ones, called a ten, and the numbers 11 to 19 are composed of a ten and one, two, three, four, five, six, seven, eight, or nine ones.

The numbers from 11 to 19 are composed of a ten and one, two, three, four, five, six, seven, eight, or nine ones.

Decompose numbers less than ten in more than one way.

The numbers 10, 20, 30, 40, 50, 60, 70, 80, 90 refer to one, two, three, four, five, six, seven, eight, or nine tens (and 0 ones).

Compare two two-digit numbers based on meanings of the tens and ones digits, recording the results of comparisons with the symbols >, =, and <.

Compare two numbers from 1 up to at least 20based on meanings of the tens and ones digits.

For example, 20 is greater than 15 because two tens is bigger than one ten and a five.

Use place value understanding and properties of operations to add and subtract.

Number & Operations in Base Ten: Use place value understanding and properties of operations to add and subtract.

Add within 100, including adding a two-digit number and a one-digit number, and adding a two-digit number and a multiple of 10, using concrete models or drawings and strategies based on place value, properties of operations, and/or the relationship between addition and subtraction; relate the strategy to a written method and explain the reasoning used. Understand that in adding two-digit numbers, one adds tens and tens, ones and ones; and sometimes it is necessary to compose a ten.

Add within 10 using concrete models or drawings.

Relate the strategy to a written method and explain or indicate the reasoning used.

Given a two-digit number, mentally find 10 more or 10 less than the number, without having to count; explain the reasoning used.

Given a single digit number, find 10 more than the number. Given a number in the range 10-20, find 10 less than the number.

Subtract multiples of 10 in the range 10–90 from multiples of 10 in the range 10–90 (positive or zero differences), using concrete models or drawings and strategies based on place value, properties of operations, and/or the relationship between addition and subtraction; relate the strategy to a written method and explain the reasoning used.

Subtract multiples of 5 in the range 5-20 from multiples of 5 in the range 5- 20 (e.g., 20-10, 15-10, 10-5), using concrete models or drawings.

Relate the strategy to a written method. Example: given 15 objects, have students subtract 10 objects that match that operation to a card with “15 - 10 = 5” written on it.

Represent and solve problems involving addition and subtraction.

Operations & Algebraic Thinking: Represent and solve problems involving addition and subtraction.

Use addition and subtraction within 20 to solve word problems involving situations of adding to, taking from, putting together, taking apart, and comparing, with unknowns in all positions, e.g., by using objects, drawings, and equations with a symbol for the unknown number to represent the problem.

Use addition and subtraction within at least 10 to solve word problems involving situations of adding to, taking from, putting together, taking apart, and comparing by using objects and drawings.

Solve word problems that call for addition of three whole numbers whose sum is less than or equal to 20, e.g., by using objects, drawings, and equations with a symbol for the unknown number to represent the problem.

Solve word problems (given orally, visually, or as objects) that call for addition of three whole numbers whose sum is up to at least 10 by using objects and drawings.

Understand and apply properties of operations and the relationship between addition and subtraction.

Operations & Algebraic Thinking: Understand and apply properties of operations and the relationship between addition and subtraction.

Apply properties of operations as strategies to add and subtract. (Students need not use formal terms for these properties.)

Apply properties of operations as strategies to add and subtract (students need not use formal terms for these properties).

Examples: If 4 + 3 = 7 is known, then 3 + 4 = 7 is also known (commutative property of addition). To add 5 + 2 + 3, the second two numbers can be added to make a 5, so 5 + 2 + 3 = 5 + 5 = 10 (associative property of addition).

Understand subtraction as an unknown-addend problem.

Understand subtraction as an unknown-added problem.

For example, subtract 5 -4 by finding the number that makes 5 when added to 4.

Add and subtract within 20.

Operations & Algebraic Thinking: Add and subtract within 20.

Relate counting to addition and subtraction (e.g., by counting on 2 to add 2).

Relate counting to addition and subtraction using concrete models or visual representations to indicate the number that results when adding or subtracting one.

Add and subtract within 20, demonstrating fluency for addition and subtraction within 10. Use strategies such as counting on; making ten (e.g., 8+6=8+2+4=10+4=14); decomposing a number leading to a ten (e.g., 13−4=13−3−1=10−1=9); using the relationship between addition and subtraction (e.g., knowing that 8+4=12, one knows 12−8=4); and creating equivalent but easier or known sums (e.g., adding 6+7 by creating the known equivalent 6+6+1=12+1=13).

Add and subtract within 20 using objects, drawing, ten frames, and/or written methods for problems with sums and differences of ten (e.g., 5 + 5, 6 + 4, 2 + 8, 14 - 4, 17 - 7) as a foundation for operations involving place value.

Work with addition and subtraction equations.

Operations & Algebraic Thinking: Work with addition and subtraction equations.

Understand the meaning of the equal sign, and determine if equations involving addition and subtraction are true or false.

Understand the meaning of the equal sign, and use models or other strategies to determine if equations involving addition and subtraction up to at least 4 are true or false. For example, does 1 + 1 = 3? Is 4 - 2 = 2 true or false?

Determine the unknown whole number in an addition or subtraction equation relating three whole numbers.

Determine the unknown whole number in an addition or subtraction equation relating three whole numbers whose sum is up to at least 10. For example, determine the unknown number that makes the equation true in each of the equations 1 = __ = 3, 4 = 6 - __, __ + 2 = 4.

Algebra and Functions

Data, Statistics, and Probability

Geometry

Make sense of problems and persevere in solving them.

Reason abstractly and quantitatively.

Construct viable arguments and critique the reasoning of others.

Model with mathematics.

Use appropriate tools strategically.

Attend to precision.

Look for and make use of structure.

Look for and express regularity in repeated reasoning.

Number and Quantity