1.)Begin by asking students if they have any knowledge of rates. Most students should be familiar with the rates miles per hour and miles per gallon. Explain that rates are comparisons of two unlike measures, e.g., miles and gallons.
2.)Explain that they are going to make small portions of Kool-Aid of varying strengths and then taste their results. Give students the datasheet and explain how to perform the activity.
3.)Procedures for the activity:
a. Groups decide on an amount of Kool-Aid powder to add to 2 cups of water.
b. Students then add the desired amount of powder to 2 cups of water, stir thoroughly, and pour a sample of the mixture for each group member to taste. They then fill out the row for trial 1 on their datasheets.
c. Students should dispose of extra liquid in the sink or bucket provided.
d. Students repeat steps a-c for trials 2-5. Each trial should consist of a different amount of powder added to the set amount of water.
4.)After groups are finished, gather the class together. Ask each group which rate produced the best tasting drink. Compare groups’ findings by looking at their strongest and weakest mixtures. Did any groups use equivalent rates?
5.)Define rate and ratio. Give several examples of each, such as comparing the number of boys to the number of girls in the class, number of birthdays in May to number in December, number of students with a pet to those with no pet, speeds on the interstate to those in a neighborhood, and measurement ratios. Ask students to give additional examples of ratios and rates that occur in everyday life.