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Stephanie Burton
Math Learning Plan
10/30/08
Title: Long Division and the Distributive Property
Grade: 5th
Objectives:
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Students will use the distributive property to rewrite long division problems.
They will model long division problems using base-10 blocks.
Related SOL’s:
5.3 The student will create and solve problems involving addition, subtraction,
multiplication, and division of whole numbers, using paper and pencil, estimation, mental
computation, and calculators.
5.5 The student, given a dividend of four digits or fewer and a divisor of two digits or
fewer, will find the quotient and remainder.
Materials:
Base-10 blocks for each student, small white board for each student, expo marker for
each student, worksheets for each student, graph paper for each student, writing utensils
Prerequisite Knowledge: previous experience using base-10 blocks, ability to divide
numbers, understanding of the distributive property (official term: distributive property of
multiplication over addition)
Procedures:
1. Divide students into groups of 4 to 5 students.
2. Ask student groups to each define the distributive property by writing a definition
of this property on their white boards. Ask them to use the distributive property to
re-write 4 x (3 + 6).
3. Have a representative of each student group present their problems to the class
highlighting how the property works and making sure they know that they get the
same answer by computing either side of 4x(3+6) = 4x3 + 4x6.
4. Ask students how we’ve used the distributive property to solve problems in the
past and ask them to show this problem with base-10 blocks.
5. Explain that we can use the distributive property to make multiplying numbers
with multiple digits simpler. Solve “152 x 5 = ?” using the distributive property
with the class.
6. Write “445  5 = ?” on the white board. Ask students how they would solve this
problem? Ask students to solve this problem and share their answer with their
groups. Pick a student to come to the white board and solve the problem.
7. Explain that you could use the distributive property to make this problem easier
and simpler to solve. Emphasize that in this case they will be dividing each of the
parts in the parentheses by the divisor (instead of multiplying).
8. Teacher should then solve this problem using the distributive property, and show
students that they could model this problem with base -10 blocks. Compare the
result to the answer they got from the traditional method in (6) above.
9. Make sure students understand this concept by solving 3 more problems in the
same manner as detailed above, and modeling these problems with base-10
blocks.
10. Explain to students that they will now by responsible for completing problems on
their worksheets in their student groups and modeling these problems with base10 blocks.
11. Once they have completed the worksheet, the class will play a game. They will be
competing with other student groups to solve problems which the teacher writes
on the board. One student from each group will go to the front of the class, while
the remaining students in his/her group individually solve the problem on their
white boards and model the problem with base-10 blocks. Each group in which all
students correctly solve the problem, write the answer on their white boards, and
correctly model the problem with base-10 blocks, will receive a point.
12. Complete as many of these problems as time permits.
Evaluation:
1. During the lesson, check the base-10 representations as students work on the
worksheet and evaluate each student’ progress.
2. Check students’ worksheets for accuracy in using the distributive property.
3. Evaluate student base-10 models and answers as they play the class game.
*Make sure that groups are varied so that there are students of all learning levels in each
group. This will ensure that students of higher learning capacities can help students that
are having difficulties learning certain concepts.