Tuesday, March 30, 2010

Natural Resources: Over Harvesting

Set up this activity to help students understand that sometimes humans take more natural resources than nature can produce.

Put students in groups of 2 or 3. You'll need 152 pretzel sticks for each group. The pretzel sticks represent trees/lumber

Within each group, you'll need someone to be the protector of the trees - he or she will 'plant' more trees each round. You'll also need someone to be the lumberjack, who 'cuts down' trees each round. If you have a third member of the group, he or she can record the data each round; if there are only two group memebrs, they can both record as the scenario plays out.

Begin with a 'forest' (pile) of 120 trees. Additionally, the protector will have a supply of 32 more trees

During each round, the following will happen...
- The protectors will 'plant' 4 trees from their source.
- The lumberjacks will double the number of trees they are 'cutting down' each round, starting with 1.
- The recorder records how many trees are left at the end of the round.

After explaining the scenario, but before beginning the actual process, ask students to guess how many rounds it will take before there are no natural resources left.

What can we do to protect our natural resources from over-harvesting?
Here's a table you can set up to help your students record their data:

Natural Resources + Trees Added - Trees Consumed = Trees remaining

The first two rows of data should look like this:

120 + 4 - 1 = 123
123 + 4 - 2 = 125

You could also use Goldfish crackers for the activity - replace the lumberjacks with fishermen and you're all set!

1 comment:

  1. Need more details about how to start each round, scenario.