In this TV411 activity, Franklin goes to the store to purchase supplies to complete a painting job. He works with Laverne to estimate the cost of materials using rounding and uses that estimate to calculate his rate of pay based on how long the job takes him.
Estimating Costs, Estimating Profits QuickTime Video
Part I: Learning Activity
1. Read the following to your students: "Franklin asks Laverne to help him work out a budget for a job he has been offered, to paint a room in a friend's house. On a piece of paper, write down what you would need to know in order to determine if you are being paid enough to paint a room assuming you need to account for your time and the cost of supplies. How could you figure out your profit? Work in pairs." Note: Put the necessary information, such as time, cost of various supplies, and amount of pay, on the board so that the students are reminded of the important factors to consider.
2. Tell the students that they will now watch a video clip in which Franklin and Laverne discuss the costs and the profit of Franklin's painting job. Ask students to pay attention to careful details such as profits, costs, and items used for the job that are important factors in determining a budget.
3. Show the Estimating Costs, Estimating Profits QuickTime Video .
4. Distribute Handout: A Sample Budget Sheet .
5. Ask the students to work up a detailed budget for a painting job. They should estimate the costs of paintbrushes, rollers, and pans separately. They should make notes about how they rounded the estimates of the costs, and whether this will likely cause them to under-estimate or over-estimate the overall cost of the job.
6. Ask the students to work out their budget in a structured way, on the handout.
7. Discuss the students' budgets. Be sure to discuss with the students how they decide in a budget whether to round numbers up or down, and how to estimate their profit. Also consider how the students' budgets were like or unlike Franklin's, whether the budget sheet on the handout was useful to them, and why, and what differences they would make for a different kind of job. Be sure to draw on any students' experience with work and budgets.
Part II: Assessment
Assessment: Level A (proficiency): Students round off the cost of items to the nearest dollar or nearest 50 cents. Be careful to watch for students who think the answer always has to have 50 cents in it to have been rounded to the nearest 50 cents.
Assessment: Level B (above proficiency): Students apply their knowledge of estimation to compare the effects of rounding off to different levels of precision.