


What's It Worth? Thinking About Weights and Measures


  • Learn that weights and measures can be used to assess value.
  • Learn that traders must be wary of fraudulent practices.
  • Appreciate the Akan weights as works of art.


  • Drawing of Akan scale
  • Supermarket advertisements or household catalogue
  • A balance scale
  • Your classroom currency from Lesson 2
  • Art supplies (see Procedure 7.)


  • Social studies, science, economics, math


1. Explain how the Akan traded with gold-dust using weights and scales. Show students a drawing of an Akan scale and describe how traders placed the weights on it. Describe the buying and selling activity. Explain why a single transaction might take several hours of negotiating with the weights as buyer and seller tried to settle on a fair price.

2. Discuss whether gold-dust meets the currency requirements you established in Lesson 2.

3. Discuss how equipment for handling money depends on the type of currency we use. Make a list of all the equipment we use today (such as cash registers and candy machines with slots for coins) that would be useless if we traded with gold-dust.

4. Show the bronze porcupine weight. Sketch it using the proper dimensions (1 7/8 by 3 1/16 inches) so that students have an accurate idea of its actual size. Explain that many Akan weights are associated with proverbs. Discuss the meaning of the porcupine proverbs.

5. Discuss how our society uses scales to determine value. Ask students to look at packaged food and nonfood items in their own kitchens and determine which ones are sold by weight. Ask students to bring in a supermarket circular or a catalogue for household items. Ask them to identify different systems of measuring and pricing. Decide which of the systems listed below is used most often in today's stores:

  • Items sold by weight (such as 1 lb. 6 oz.)
  • Items sold by size (such as small, medium, large)
  • Items sold by quantity (such as package of three for $5)
  • Items sold by quality (such as "good" for $4; "best" for $6)

6. Purchase or build with containers a balance scale for weighing your class currency. You can make an Akan-style scale with plastic pails or foil pie tins suspended from a stick by strings, or you can use a self-standing scale. Check your scale's accuracy. Do nine single paper clips chosen at random balance three chains of three paper clips? (They should.) Do any six rocks chosen at random balance any other six rocks? (They probably won't.)

7. Ask each student to build his/her own weight in the shape of an animal or an easily identifiable object. If your classroom currency is very light, you might make the weights out of something light like styrofoam. If your classroom currency is heavy, you might make the weights out of clay. Students might compose proverbs for their weights.

Ask each student to make his/her weight exactly equal to some multiple of your class currency. (For example, one weight might equal twenty large paper clips and seven small paper clips.) Each student should inform the teacher of the equivalence but keep it a secret from the other students. Have students use the scale to figure out the equivalence of each student's weight.

Smithsonian Center for Education and Museum Studies