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# Timber

## What’s the best strategy for cutting down trees?

What’s the best strategy for cutting down trees? From building houses to burning charcoal, humans have many different uses for wood. Unfortunately, trees are disappearing in many parts of the world, including the older and larger trees that are so critical to the environment.

In this lesson, student use cylinder volume to determine how the amount of wood in a tree changes as it grows and discuss how communities around the world can harvest (or not harvest) wood in a sustainable way.

### REAL WORLD TAKEAWAYS

• Humans cut down trees so they can use the wood for homes, charcoal, paper, etc.
• Trees are also valuable when they’re not cut down. Trees provide habit for animals, create oxygen, and help cool the planet.
• Trees grow with time, so more mature trees simply have more tree to them. A more mature, bigger tree will also gain more volume in a year than they it would have when it was younger and smaller.

### MATH OBJECTIVES

• Calculate the volume of a cylinder
• Solve real world problems using unit rates

Appropriate most times as students are developing conceptual understanding.