standard_description: 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.
problem_activity: Narrative
The purpose of this activity is for students to choose from activities that offer practice adding and subtracting within 10. Students choose from any stage of previously introduced centers.
Number Puzzles
Check it Off
Find the Pair
Required Materials
Materials to Gather
Materials from previous centers
Required Preparation
Gather materials from previous centers:
Number Puzzles, Stage 1
Check It Off, Stages 1 and 2
Find the Pair, Stage 2
Launch
Groups of 2
“Now you are going to choose from centers we have already learned.”
Display the center choices in the student book.
“Think about what you would like to do.”
30 seconds: quiet think time
Activity
Invite students to work at the center of their choice.
10 minutes: center work time
Student Facing
Choose a center.
Number Puzzles
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Check it Off
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Find the Pair
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Activity Synthesis
“What method do you use most often to find the value of sums you do not yet know?”


aligns: no