Lesson 2 Fluency Flip

    • Let’s add and subtract fluently.

Warm-up True or False: Sums within 20

Decide if each statement true or false. Be prepared to explain your reasoning.

Activity 1 Heads Up: Make 20


  • Partner A holds a card on their forehead without looking.

  • Partner B names the number that you can add to the number on the card to get 20.

  • Partner A says the number on their card.

  • Record an equation to represent how you found the unknown addend.

my equations

my partner’s equations

Activity 2 Number Mix Up

You are going to use your cards to complete number puzzles. You may only use numbers 0 through 9. You may only use each number one time to make all the equations true.