Measurement Brainstorm

Measurement is commonly associated with rulers, but humans have invented many different ways to measure time, volume, weight, distance, length, speed, etc. This brainstorm encourages students to become more aware of the relevant technology they use every day to measure!

Time: 10 minutes
Materials: Chart paper, markers.

Getting Started:
*Take a minute to ask students what it means to "brainstorm." Include the idea that there are no "right"or "wrong" answers, and encourage everyone to participate.
*Explain that we're going to brainstorm a list of things we use to measure. Start by asking students to think of the different things that we measure, such as:
Speed, distance, time, (air) pressure, length, weight, mass, and volume.

You may decide to look at the difference between weight, mass and volume. (FYI -- the difference between weight and mass gets into gravity, with Mass being constant and Weight varying with gravitational pull.)

*Brainstorm the "Measurers"; the machines, concepts and units invented by humans to assist us in our measurements.

*Hints for getting started: Encourage students to think of different rooms in their houses and what they contain, cars and buses, streets and cities.

Here are some ideas in case you get stuck:

*calendars
*months
*days
*hours
*stopwatches
*rulers
*inches
*standard clocks
*thermometers
*numbers!

...Who invented numbers, anyway????

PRETZEL FIELD

Materials: Graph paper, string, rulers, pencils, pretzels, other manipulatives, and scissors.
Time: 35 minutes

Getting started:
Tell the students you are going to ask them to solve a problem. They will be able to use any of the materials that are available to them, and will work in groups which will have to present their solutions to the rest of the class.

Tell the following story to your students:
You have been asked to purchase a piece of green, fertile farming land for your boss. Your boss, Ms. Twist, happens to be the owner of "#1 Pretzel of California." She invented a plant which grows pretzels (salt and all!), and she's been so successful, she can now expand her farm, in order to grow more pretzels.

Ms. Twist always buys her land from the Rectangle Land Corporation (or RLC). RLC only sells land in rectangular packages. The buyer (in this case, YOU!) must select the length and width of the piece of land. Your boss tells you that she has enough money in the budget to purchase a piece of pretzel growing land with a perimeter of no more than 30 feet. She needs you to write up a proposal specifying the dimensions of the RLC land package which will allow her to maximize the number of pretzels she can grow.

The Challenge: Decide what your boss' best bet will be, in terms of dimensions of the rectangular field. (see "**Hints", below)
What should the length be?
What should the width be?
Each group must present it's decision, with an explanation of WHY, in the last 10 minutes of SMART.

**Hints for getting started:
Have students practice drawing any rectangle with a perimeter of 30 units on a piece of graph paper. Define perimeter. (cont on next pg...)

*Define what length and width are, when it comes to rectangles.
*Encourage students to take their time, explore lots of different shapes and sizes, and use pretzels and work on graph paper to explore the idea of area...(the area in this case is the number of pretzels that fit into the shape...but how does it relate to perimeter?)

Extensions: What if you do a little research and discover that another Realtor, CLC (Circle Land Corporation) has prices that are just as good as RLC? Circle Land Corporation only sells circular land packages and uses outer edge (circumference) measurements to determine pricing. Would Ms. Twist be better off buying a circular plot of land? How could you find out?

To Discuss: What was your group's strategy in deciding which shape would grow the most pretzels? What did you find out along the way?