Workshop: Subtraction Practice

Display the Subtraction Practice Workshop Menu from the Student Activity Book again. Provide an overview of students’ practice choices in the second column. The activities in the second column provide practice with using mental math and paper-and-pencil subtraction strategies.

Both of the activities require students to solve the same problem two ways. This expands students’ proficiency with a variety of strategies and encourages them to consider the efficiency of strategies. It also encourages students to compare strategies, check for reasonableness, and check for and correct mistakes.

Students may choose to solve problems from Part 1 or Part 2 of the Subtraction Strategies Practice pages in the Student Activity Book. Part 1 provides practice with subtracting mainly two-digit numbers and making up to one trade. Part 2 involves subtracting two- and three-digit numbers with up to two trades and is more challenging. It also asks students to consider which strategy is more efficient. Ask students to consider their confidence levels with these skills when choosing between the two. If time, some students may choose to do both sections.

Tell students to remove the Subtraction Practice Workshop Menu page from the Student Activity Book. Ask each student to choose and then circle one activity from the second column. Encourage students to refer to the Subtraction Strategies Menu in the Student Activity Book Reference section as they work, and to use tools as needed such as the 200 Chart, number lines, and base-ten pieces. As they begin working, circulate and monitor student choices.

Upon completion, discuss the advantages and disadvantages of the strategies chosen for particular problems.

Unfinished problems from Part 1 or Part 2 of the Subtraction Strategies Practice pages can be assigned as homework. Include a copy of the Subtraction Strategies Menu from
Lesson 7.

Have students save their Subtraction Practice Workshop Menu for the third session of the Workshop.