Activity on Paper or Plastic
By John Cowens

To view John Cowens' article on Paper or Plastic? click here.

This activity makes a great intermediate-level science fair project because it precisely measures volume and the mass of paper and plastic pieces.

Materials:

• plastic bags


• paper bags


• scissors


• 50mL Pyrex® beaker (or equivalent)


• triple-beam balance


• two large, heavy marbles


• two cardboard circles that fit inside the 50mL beakers

Procedures:

1. To set the stage for this activity, ask your students the following questions:
   (a.) What do you suppose environmentally conscious consumers might ask before choosing plastic or paper bags at the grocery store?

   (b.) Which is easier to transport – plastic or glass soda bottles? Why?

   (c.) After emptying items from either a plastic or paper bag, what happens to the bag?

   (d.) Why do you think people throw away materials that could easily be recycled?

   (e.) Why are landfills filling up at a rapid rate?

   (f.) Why does it take a long time for buried trash to decompose in landfills?

2. Cut a standard-size paper grocery bag and a standard-size plastic bag with scissors so that both are 12 inches x 12 inches (30 cm x 30 cm). Then, cut them into one-inch (2.5 cm) squares. (The students should end up with 144 paper squares and 144 plastic squares.)
3. Place and pack the paper squares firmly into a 50 ml Pyrex beaker. Place and pack the plastic squares firmly into the other 50 ml Pyrex beaker. To help pack the squares, cut out a cardboard circle that fits inside the beakers. Use a large, heavy marble to press the squares to the bottom of the beakers.
4. Record in the Data Table the number of milliliters of space occupied by the paper squares.

5. Remove and weigh the paper squares together. Record the mass of the paper in the Data Table.

6. Repeat steps 2 - 5 with the one-inch plastic squares.

Assessment:

1. Which is heavier, the plastic or paper bags? How much heavier?
2. Which takes up more space, the plastic or the paper bags? How much more space?
3. If landfill space were the only consideration, would it be more environmentally correct to package your groceries in paper or plastic? Why?
4. If fuel conservation were the only consideration, would it be more environmentally correct to package your groceries in paper or plastic? Why?
5. How much space did the paper bags occupy in cubic centimeters? How much space did the plastic bags occupy in cubic centimeters?

To view John Cowens' article on Paper or Plastic? click here.

John Cowens teaches sixth grade at Fleming Middle School in Grants Pass, OR.

April 2007, Vol.37, No.7