1st Grade Math (Colorado Academic Standards)

Standard 1: Number and Quantity

• MA.1.NBT.A Extend counting to 120.
  • 1. Count to 120 from any number below 120; read and write numerals and use them to show amounts in that range.
• MA.1.NBT.B Understand tens and ones in two-digit numbers.
  • 1. Know that in a two-digit number one digit counts tens and the other counts ones.
  • 1.a. See 10 as one bundle of ten ones, which we call a "ten".
  • 1.b. Know 11–19 are made of one ten plus one to nine ones.
  • 1.c. Know 10, 20, … 90 mean one to nine tens and no ones.
  • 2. Compare two two-digit numbers using tens and ones, recording with >, = and <.
• MA.1.NBT.C Add and subtract using place value and properties of operations.
  • 1. Add within 100 (two-digit plus one-digit or plus a multiple of 10) with models and place-value strategies, explaining reasoning and composing a ten when needed.
  • 2. Find 10 more or 10 less than a two-digit number mentally and explain how.
  • 3. Subtract multiples of 10 from multiples of 10 (10–90) with models and place-value strategies, explaining the reasoning.

Standard 2: Algebra and Functions

• MA.1.OA.A Represent and solve addition and subtraction problems.
  • 1. Solve add/subtract word problems within 20 of all situation types, with the unknown in any position, using objects, drawings and equations.
  • 2. Solve word problems that add three whole numbers with a total of 20 or less.
• MA.1.OA.B Use properties of operations and link addition to subtraction.
  • 1. Use properties of operations (commutative, associative) as strategies to add and subtract.
  • 2. See subtraction as finding an unknown addend (e.g. 10 − 8 by asking what adds to 8 to make 10).
• MA.1.OA.C Add and subtract within 20.
  • 1. Connect counting to addition and subtraction, such as counting on to add.
  • 2. Add and subtract within 20, fluent within 10, using strategies such as counting on, making ten and related facts.
• MA.1.OA.D Work with addition and subtraction equations and the equal sign.
  • 1. Understand the equal sign and decide whether addition and subtraction equations are true or false.
  • 2. Work out the missing number in an add or subtract equation such as 8 + ? = 11.

Standard 3: Data, Statistics, and Probability

• MA.1.MD.A Measure lengths by comparing and by repeating a length unit.
  • 1. Put three objects in order by length and compare two lengths indirectly using a third object.
  • 2. Measure length as a whole number of same-size units laid end to end with no gaps or overlaps.
• MA.1.MD.B Tell and write time.
  • 1. Tell and write time to the hour and half hour on analog and digital clocks.
• MA.1.MD.C Organize, show and interpret data.
  • 1. Organize and interpret data in up to three categories and answer questions about totals and differences.

Standard 4: Geometry

• MA.1.G.A Reason about shapes and what defines them.
  • 1. Tell defining attributes of shapes from non-defining ones (e.g. color, size) and build and draw shapes with given attributes.
  • 2. Combine 2-D or 3-D shapes to make a composite shape and make new shapes from it.
  • 3. Split circles and rectangles into 2 or 4 equal shares, call them halves, fourths or quarters, and see that more shares are smaller.