Author: Terra Shea DeSpain-Lyon, University of North Texas, March 27, 1996
Grade Level: 5-7
Overview: Many students can test well on multiplying and dividing fractions, but when it comes to real life situations do not understand how to use their knowledge.
Purpose: To assess students' working knowledge of fraction multiplication and division.
Objective: Students will be able to apply what they've learned about fractions to a real life situation.
Materials: Measuring cups, measuring teaspoons, measuring tablespoons, ingredients for a choosen recipe, access to an oven and refrigerator.
Activities and Procedures:
- Review adding, subtracting, multiplying, and dividing fractions with the class.
- Discuss with students where they see fractions in life.
- Have students look at measuring utensils. Question students on where they've seen these and what they are used for.
- On an overhead or board, you and the class must convert a recipe to feed the class. For example, If a recipe makes three and a half dozen cookies, how many cookies is this? (42) If there are 21 students in the class and they can eat five cookies apiece, how many cookies do we need? (105) If one batch makes 42 cookies, how many batches do we need? (2 1/2) They have to multiply each fraction in the recipe by 2 1/2.
- Split the class into four groups. On paper, the first group halves the recipe, the second group doubles the recipe, the third group makes the recipe feed the entire grade level for the school, and the last group converts the recipe to feed 50.
- After the groups finish, discuss these out loud to let each group hear how the other groups did this.
- Make the recipe in class that you converted on the overhead. The students do the measuring and mixing with teacher supervision.
- Give assignment. Each student takes a recipe from home and does this again on his or her own. They do the things we did in class: halve it, double it, make it feed the whole class, and make it feed the whole grade level. This is great for an end of the unit project on poster board, well presented. Grade mostly on fractional conversions but on neatness as well.
Note: Have some copies of recipes for students to take home if needed. They may not have access at home. Here is a good recipe to use with lots of nice fractions and easily made in school:
1 C butter or margerine, softenedCream together liquid ingredients from top half of recipe. In a separate bowl, mix dry ingredients. Gradually add dry ingredients to wet ingredients and then add nuts. Do the same with the bottom ingredients. Spread half of the first batter into a greased baking pan. Spread second mixture over chocolate mixture. Then spread the remaining of the first mixture over the top. Swirl with a spatula or fork. Bake at 350 for 40 to 50 minutes or until brownie pulls away from side. Cool in pan. Cut in squares.
2 C granulated sugar
2 t vanilla
1 1/3 C flour
3/4 C Hershey's Cocoa
1 t baking powder
1/2 t salt
2/3 C chopped nuts, optional
1/3 C butter or margerine
2 (3-ounce) packages of cream cheese softened
1/3 C granulated sugar
2 T flour
3/4 t vanilla
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