In this second lesson, students are given several samples of wood. The students' goal is to identify the species of wood blanks they're working with and recognize the different grain patterns that influence wood strength.
LUMBER QUALITIES AND CHARACTERISTICS
The qualities of different types of lumber are as different as night and day. Students may have flown their first toy glider made from balsa wood - it's light, soft and flexible, and they may have used a cutting board made from Maple. Maple and Balsa are similar in color, but there's a reason we don't build toy gliders out of Maple, and we don't make cutting boards out of Balsa wood.... Some species are better than others for bending, and students will learn which species have better characteristics for bending.
In this lesson, students will match unmarked wood blanks of different woods with others that are named, so that they can visually identify the species of lumber by looking at a board. This lesson builds on the photos they used to identify trees in lesson 1, by matching actual samples of the wood.
In addition, grain direction is a source of strength in a board, and the grain direction is determined by how the log is sawn into boards at the lumber mill. Students test grain strength and learn how grain orientation influences overall wood strength. They get to break something and not get in trouble!
[Additional information for the instructor and a material list is included in collections under resources. It is titled "Lesson 2, Materials and Instructor Resources"]