standard_description: 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.
problem_activity: Stage 1: Any Way
Required Preparation
Materials to Gather
Collections of objects
Materials to Copy
Blackline Masters
Sort and Display Stage 1 Recording Sheet

Narrative
Students sort 10–20 objects into two or three categories and then show how they sorted. Provide students with a group of items that will be interesting for them to work with such as:
pattern blocks
connecting cubes
counters
combination of the blocks, cubes, and counters
sets of books
Students then show their representation to a partner and ask questions that can be answered about their collection of objects.
Additional Information
Create collections of 10–20 objects with up to three attributes by which to sort.


aligns: no