Fraction Multiplication (Script)

Summer 2012 Fraction Multiplication (Script)

Materials Needed: Make copies of the Fraction Multiplication Handout. Provide square tiles, fraction strips, Cuisenaire rods, colored markers, fraction grids, and grid paper for participants to use in constructing models of the problems. Also provide chart paper and index cards with the following problems written on them (make 3 of each problem) for presentations:

Activity: Ask participants what 3x4 means. Ask them to draw a picture, build a model, or give a word problem to show the meaning. Listen to ideas and capitalize on ideas that emphasize 3x4 means 3 groups of 4.

Have participants work in pairs to draw a picture or use manipulatives to represent each of the questions being asked below. Plan to share results with the whole group. 1. There are 15 teachers at a professional development. of those teachers have brown eyes. How many of the teachers have brown eyes? of 15 2. Kevin filled 15 glasses with pints of soda in each glass. How may pints of soda did Kevin use? added 15 times 3. A flower garden is to be seeded that is 15 meters by of a meter. How much area is to be seeded? (Area) AV0023 4.

Have participants partner up with someone and share their results then discuss the similarities and differences in the 3 problems.

In all of the above problems, we were multiplying a fraction by a whole number. Next we explore problems with 2 fractions.

Distribute the Fraction Multiplication Handout to participants and ask them to work with a partner to solve the problems on the handout and be prepared to explain their thinking to the rest of the whole group. Encourage the use of both words and pictures to help them think through the problems and show how they solved them.

As participants are working, look for pairs who use different representations to think about the problems. Make a note so you can call on these participants to share later. Ask 3-6 pairs to share their solution to one of the problems with the whole group.

Now ask participants to work in groups of 3-4 to create a word problem whose solution is the expression on the card they have been given:

Fraction Multiplication Script Page 1 of 2 Summer 2012 Ask groups to write their problem on poster paper and include how they would explain how to solve problem to their students (grade-level appropriate). Have groups hang their posters on the wall, clustering the posters together that illustrate the same multiplication problem. Have participants do a Gallery Walk where they examine the posters and notice any similarities or differences in the word problems and the explanations.

Extension: Have participants consider the connection between fraction multiplication done in this activity to whole-number multiplication, specifically with the “Generic Rectangle”, which also connects to the Distributive Property. For example, if we consider the problem

we could rewrite it as then draw the following generic rectangle. As in whole number multiplication, we see the Distributive Property at work when writing out the partial products.