standard_description: Add and subtract within 1000, 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. Understand that in adding or subtracting three-digit numbers, one adds or subtracts hundreds and hundreds, tens and tens, ones and ones; and sometimes it is necessary to compose or decompose tens or hundreds.
problem_activity: Stage 2: Three-digit Numbers
Required Preparation
Materials to Gather
Number cards 0–10
Materials to Copy
Blackline Masters
Mystery Number Stage 2 Directions

Narrative
Students pick three cards and make a mystery three-digit number. Students give clues based on the sentence starters.


aligns: no