## Tens & Ones

Understand that the two digits of a two-digit number represent amounts of tens and ones. Understand the following as special cases: A. 10 can be thought of as a bundle of ten ones — called a “ten.” B. The numbers from 11 to 19 are composed of a ten and one, two, three, four, five, six, seven, eight, or nine ones. C. 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).

## Counting to 120

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.

## Adding Within 100

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.

## Subtract Multiples of 10

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.

## Comparing Numbers

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

## Mental Math

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

## Length of an Object

Use nonstandard physical models to show the length of an object as the number of same size units of length with no gaps or overlaps.

## Ordering Objects by Length

Order three objects by length using indirect comparison.

## Tell and Write Time

Use analog and digital clocks to tell and record time to the hour and half hour.

## Interpreting Data

1.MDA.4 Collect, organize, and represent data with up to 3 categories using object graphs, picture graphs, t-charts and tallies.

1.MDA.5 Draw conclusions from given object graphs, picture graphs, t-charts, tallies, and bar graphs.

## Number Sentences

1.ATO.7 Understand the meaning of the equal sign as a relationship between two quantities (sameness) and determine if equations involving addition and subtraction are true.

1.ATO.8 Determine the missing number in addition and subtraction equations within 20.

## Properties of Operations

Apply Commutative and Associative Properties of Addition to find the sum (through 20) of two or three addends.

## Addition and Subtraction Word Problems

Solve real-world/story problems using addition (as a joining action and as a part-part-whole action) and subtraction (as a separation action, finding parts of the whole, and as a comparison) through 20 with unknowns in all positions.

## Adding and Subtracting within 20

1.ATO.4 Understand subtraction as an unknown addend problem.

1.ATO.5 Recognize how counting relates to addition and subtraction.

1.ATO.6 Demonstrate: a. addition and subtraction through 20; b. fluency with addition and related subtraction facts through 10.

## Adding Three Whole Numbers

Solve real-world/story problems that include three whole number addends whose sum is less than or equal to 20.

## Partitioning Into Equal Shares

Partition two-dimensional shapes (i.e., square, rectangle, circle) into two or four equal parts.

## Shape Attributes

Distinguish between a two-dimensional shape’s defining (e.g., number of sides) and non-defining attributes (e.g., color).

## Composite Shapes

Combine two-dimensional shapes (i.e., square, rectangle, triangle, hexagon, rhombus, and trapezoid) or three-dimensional shapes (i.e., cube, rectangular prism, cone, and cylinder) in more than one way to form a composite shape.