standard_description: Determine the unknown whole number in an addition or subtraction equation relating to three whole numbers. For example, determine the unknown number that makes the equation true in each of the equations 8 + ? = 11, 5 = �� – 3, 6 + 6 = ��.
problem_activity: Narrative
The purpose of this activity is for students to choose from activities focusing on two-digit numbers. Students are introduced to stage 3 of the Target Numbers center. Then students choose between that center or others previously introduced.
Students choose from any stage of previously introduced centers.
Target Numbers
Number Puzzles
Mystery Number
Required Materials
Materials to Gather
Connecting cubes in towers of 10 and singles
Materials from previous centers
Number cubes
Materials to Copy
Target Numbers Stage 3 Recording Sheet
Required Preparation
Gather materials form previous centers:
Target Numbers, Stages 1-2
Number Puzzles, Stages 1-4
Mystery Number, Stage 1
Launch
Groups of 2
“Today you will choose from centers we have already learned. One of the choices is to play Target Numbers in a new way. Just like last time, your target number is 95. You will roll two cubes to get your starting number. Then, on each turn, roll three cubes and choose one of the numbers to represent the tens and another number to represent the ones. Add the new number you made to your starting number and record your equation. Continue playing for six rounds to see who gets closest to 95 without going over.”
Display the center choices in the student book.
“Think about what you would like to do first.”
30 seconds: quiet think time
Activity
8 minutes: center work time
“Choose what you would like to do next.”
8 minutes: center work time
Student Facing
Choose a center.
Target Numbers
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Number Puzzles
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Mystery Number
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Activity Synthesis
“What did you like about the centers you chose?”


aligns: yes