Materials
empty 2-liter soda bottle
spring-type clothespin
thin dowel or skewer
hole punch
2 paper cups
string
scissors
2 packing peanuts
various items to weigh, such as
paperclips, coins, cotton balls, blocks,
erasers, and so on
paper and pencil
Instructions
1. Rinse out the soda bottle and let it dry.
2. Put the clothespin, pinch-side down, in
the mouth of the bottle.
3. Push the dowel through
the hole in the clothespin
to its mid-point.
4. Punch three holes around
the top of each cup, spacing
the punches evenly.
5. Cut six pieces of string into
equal lengths.
6. Insert one end of the string through the hole of one cup and tie a knot.
Insert the other two strings into the other two holes and do the same thing.
7. Tie the other ends of the three strings together in a knot. Do this for both
cups.
8. Hang the cups on opposite sides of the dowel.
9. Put a packing peanut on each end of the dowel to hold the cups onto the
dowel.
10. Encourage the children to experiment with weighing various items. What
weighs more? Less? The same?
11. The children can chart their results on paper.
