Estimation Contest
Time: 20-25 minutes
Materials:
Box of plain cheerios / Clear plastic container / Prizes: pencils, stickers, ribbons / Plastic Bag or small cup / Pen or pencilDirections
- Using a 4-oz. cup as a measure, put enough cereal rings to fill the 4-oz. cup plus a little more into a plastic sandwich bag for each pair of youth.
- Ask the youth how they prepare a breakfast of cereal. Ask them how much cereal they pour into their bowls. How do they know how much milk to add?
- Do they measure out the amount of cereal or milk? Do they have to be exact in the amounts of cereal and milk that they use?
- Of course, one does not have to be exact to make a bowl of cold cereal-simply estimating a reasonable amount is all that it takes.
- Point out to them that when they prepare a cereal breakfast, theysimply estimate, rather than measure out exactly, the amounts of cereal and milk.
- Ask them to list aloud other daily situations in which .they use estimation. Most daily problems do not require an exact or single answer-close enough is all that it takes to solve the problem. It would take too much effort and time to figure out everything exactly.
- Tell them that in today's activity, they will get to practice their estimation skills.
- Distribute a zip lock bag of cheerios to each group. Show the whole group a 32 oz. container of cereal. Ask them to estimate how many cheerios are in that container.
- Have each group write down their estimation. Once everyone has a guess have them share the number they wrote. Then reveal how many cheerios are in the container.
Extended Activity
- Estimate the average speed at which you will travel between your house and the airport. For example, if most of the way to the airport is on a freeway or highway, your average speed may be about 50 miles per hour; if it is mostly city streets, then your average speed may be about 35 miles per hour.
- 11ultiply the average speed times the number of miles between your house and the airport, 60 miles in this case. The answer will give you an estimate of the amount of time needed to travel to the airport.
- Add the travel time to the 60 minutes or 1hour that is needed after you arrive at the airport to check-in and walk to the plane's gate.
- Subtract the total amount of time needed for travel to the airport and check-in from the flight time of 10:30. Looking at a non-digital clock or watch may help you figure out the time that you would have to leave your house to catch a 10:30 flight. Happy travels!
Discussion
To figure out how many cereal rings are in the 32-oz. container, you need to divide the volume of the container, 32-oz., by the volume of the cup. Then, multiply that answer by the number of cereal rings that will fit in the cup. If the cup does not divide evenly into the container, the youth will need to "round off ' and take that into account when they come up with their final answer. Remember that in estimating, getting a reasonable answer is more important than getting the exact answer. Depending on the size of the container and the ages of the youth, a reasonable answer may be anything within 200 cereal rings of the exact answer.
There will be many reasonable answers, and so, many prize winners!