The purpose of this activity is for students to learn Stage 2 of the How Close? center. Students start with 4 number cards and then choose 2 or 3 of those numbers to subtract from 20 to get as close as possible to 0, the target number. The student with a difference closest to zero wins a point for the round. Before playing, students should remove cards that show 10 from their deck and set them aside.

• Display number cards 6, 4, 9, 8
• “Which cards would you use and why?” (9 and 8 are the biggest numbers so that would get me close to 0. 6 and 4 make 10 and if we include 9 that would get us closer to 0.)

The purpose of this activity is for students to learn Stage 2 of the Compare center. Students choose a card with either an addition or subtraction expression within 20 and compare the values. The partner whose card has the greater value takes both cards. The game is over when each partner runs out of cards to flip over. The partner with the most cards wins. After learning this new stage of the Compare center, students then choose from other activities focused on addition and subtraction.

Students choose from any of the previously introduced stages of the listed centers.

• Compare
• How Close?
• Five in a Row

• Display and .
• “Which card has the greater value? How do you know?”