Add and Subtract Decimals with Paper and Pencil

Introduce Add or Subtract to 1 Game. Display the Add or Subtract to 1 Game pages from the Student Activity Book. You will need the display deck of digit cards that you prepared prior to the lesson. See Materials Preparation. Read the directions to the game aloud. Shuffle the cards and ask a student volunteer to play a demonstration game with you. Each player uses 6 cards to make an addition or subtraction problem on the game board. Players solve their problems and the player whose sum or difference is closest to 1 takes all the cards. Explain to students that sums or differences can be more than or less than 1, and that they will need to determine which player's answer is closest to 1. Use the example round on the directions page to discuss how to determine whether 1.02 or .906 is closer to 1. See Figure 4 for another sample round. The player with the most cards at the end of the game wins.

Play Add or Subtract to 1 Game. Students play the game with a partner. Remind students that they can refer to their My Decimal Strategies Menus and use any tools they have used during the lesson as they play the game.

Discuss Game Strategies. After students have had an opportunity to play the game, discuss strategies.