Solving Subtraction Problems

Explicit Instruction/Teacher modeling

• Model solving the problem while reviewing the vocabulary for subtraction. For example, "Subtraction means to take numbers away."
• Review the differences between subtraction and addition by writing up an addition equation and saying, "Addition means to put numbers together."
• Ask students to create a movement for addition and subtraction. For example, addition put hands together, subtraction put hands behind their backs.
• Solve the same problem again, this time using a new strategy (e.g., number line). Explain to students that there is always more than one way to solve a problem. We call this using a strategy or a plan.

Guided Practice

• Write up a new subtraction equation such as 4 - 2 = ____ on the board.
• Ask students to think-pair-share with a partner to decide how to solve the problem.
• Create a subtraction strategy anchor chart (e.g., draw a picture, use a number line, use your fingers, count back, or use manipulatives) to refer to throughout the lesson.
• Solve the problem with group input. Practice reading the equation as a group.

Group work time

• Display the Space Item Subtraction worksheet and go over instructions.
• Have students work alongside a partner to complete their worksheets independently. When finished, ask pairs to think back on the lesson and their strategy anchor chart as they turn and talk using the following sentence starters, "I solved my problem by using ____. Something that was tricky for me was ___."