Lesson Plan

An exercise in inverting one’s thinking

All Notes

Teacher Notes

Student Notes

Slice It!

Free, Paid

Review the concept of fractions – part of a whole – with **Slice It!** Have students test their spatial skills by splitting unconventional into equal parts. Reinforce key vocabulary such as numerator, denominator, and equivalent.

Khan Academy

Free

In order to understand how fractions are divided, ask students to reconceptualize integer division problems. For instance, when trying to solve 12 ÷ 3, show that you are actually trying to figure out how much 1/3 of 12 is. For division problems, fractions and otherwise, we are actually multiplying by the inverse 12 ÷ 3 = 12 x 1/3. This tactic will set the foundation for more complex problems. Next, demonstrate how to apply this procedure to dividing an integer by a fraction: 2 ÷ 4/5 = 2 x 5/4 or 2/1 x 5/4. Finally, apply this process to dividing one fraction by another: 3/5 ÷ 1/4 = 3/5 x 4/1. Again, the rule of thumb is: find the inverse (or reciprocal) of the divisor (second number), then multiply. Show **Khan Academy’s** video, *Dividing Fractions* (8:59). Follow up with several practice problems, and try to apply to real world examples. When possible, diagram the quotients with rectangles to show how to simplify the answer (especially when changing improper fractions into mixed numbers). Make sure to introduce key vocabulary as necessary: inverse, invert, reciprocal, dividend, divisor, quotient.

ExploreLearning Gizmos

Free to try, Paid

Have students work in small collaborative groups to experiment with **Explorelearning’s** Dividing Fractions Gizmo (http://www.explorelearning.com/index.cfm?method=cResource.dspDetail&ResourceID=1006). This interactive will give students a visual model to help explain the rule for dividing fractions (find the inverse of the divisor, then multiple). Together, students should answer the accompanying Student Exploration: Dividing Fractions packet.

Educreations

Free

Have students create their own tutorial videos for dividing fractions with **Educreations** **Interactive Whiteboard**. They can record themselves explaining the problem solving process, including any tips and hints they value. They can end with challenging practice questions for fellow classmates.

Mangahigh

Free, Free to try, Paid

Student can play with **Managhigh’s** *Division with Fractions* game, receiving scaffolded support as they go. Players earn more points with increased speed, increased difficulty (three levels), and by solving three problems in a row.