# Wood Identification Based on Density

Keywords: mass, volume, density, characteristic properties; Lesson Plan Grade Level: eighth; Setting: classroom

## Goals for the Lesson

- Students will measure length, width and height in centimeters
- Students will identify regular versus irregular shaped solids
- Students will calculate volume by multiplying length x width x height
- Students will calculate mass in grams
- Students will calculate density in grams per cubic centimeter

## Materials Needed

- metric rulers
- four beam balance
- wood samples of five different species
- calculators
- data chart

**
State Standards Addressed:
**
Science and Technology; Inquiry and Design (3.2.10)

**
Teaching Model:
**
Traditional

**Subjects Covered:
**
biology, mathematics

**
Topics:
**
botany, density, linear measurement, mass measurement

## Preparation

- All wood species will be cut into regular shaped pieces.
- All species will be kiln dried to the same moisture content
- All students will practice measuring in grams.
- All students will practice measuring in centimeters.
- All students will practice the density formula (density = mass/volume)
- All students will make data sheets to record mass, length, width, height, volume, density,
- sample number.
- All blocks of the same species should have the same number marked on the block

## Activity

- Review the formulas needed to calculate volume and density.
- Place students in groups on two or three.
- Give each group calculators, metric rulers, balances, and five different wood samples.
- Have each group record length, width and height for each sample to the nearest 0.1 centimeter.
- Have each group mass each sample to the nearest 0.01 gram and record.
- Have the students calculate volume in cubic centimeters and record.
- Each group can now calculate density by using the density formula and record in grams per cubic centimeter.

## Assessment

Have students match their densities to a handout with seven or eight different wood species with their densities attached. Collect data sheets and check densities.

## Conclusion

Discuss the following:

- Size does not affect density.
- Density can be used to identify many things.
- How does density affect the use of different species?
- Which errors could influence density calculations?

## Author

Alex Fox, Mifflin County School District