Students build a bent-wood back scratcher in this lesson series. There are four lessons in this PBL group. Students will learn that not all woods are suitable for bending.
In this lesson, students learn of different tree species and become familiar with woods used in woodworking, and learn which woods make suitable back scratchers. Depending on how many woods are identified and class size, this lesson can be completed in a period. Greater depth of identification or more species of trees.
A back scratcher should be strong, yet be able to bend - not all woods bend well or will work.
The objective of this lesson is for students to differentiate and identify different species of trees and types of lumber visually - Looking at pictures and illustrations of a given trees' leaves, flowers, fruit/nut/seed, general tree structure or other identifying element - such as the white bark you'd find on a Birch tree, or the peeling bark of a Eucalyptus.
This foundation gives student the groundwork to evaluate "Which Wood?" might work best for their back scratcher project. Students look at cards with a variety of un captioned photos of these elements, then match them with named pictures.
The instructor should emphasize that the different species of woods have wildly different qualities, and different uses based on those characteristics. This lesson provides ways to identify and evaluate woods, and strongly demonstrate the differences between species. Students scaffold this information to build on the core of the next lesson. In lesson 2, students will identify species and grain patterns in a variety of wood samples, using small samples of wood.
The activities and these lessons can be simplified or made more complex, depending on student ability. Students may work alone, in groups, or collaborate as a class.