Strategies for Adding and Subtracting Decimals

Introduce the Game. Students practice representing adding and subtracting decimal numbers on number lines in the Start, Hop, Stop to Hundredths game. This helps build strategies for composing and decomposing decimal numbers according to place value, and develops foundations for adding and subtracting decimals.

Display and read the directions for the game on the first page of the Start, Hop, Stop to Hundredths pages in the Student Activity Book. Display the spinners and a game board page to demonstrate playing a few turns of the game as you read through the directions. See Figure 5 for a sample turn. Remind students of the following important points as they become familiar with the game:

• There is usually more than one path from the start point to the stop point.
• The object is to move from the start point to the stop point in as few hops as possible.
• Only hops of one-hundredth and one-tenth are permitted.
• Hops can be both forward and backward.
• Students must record a number sentence for each turn.

Play the Game. Students play the game with a partner. Have students take turns spinning the spinner. As students play the game, check whether students show understanding of place value in decimal numbers.

Make additional copies using the Start, Hop, Stop to Hundredths Game Board Masters if you want students to play additional times in class or at home.