Keywords: wood, cellulose, hemicellulose, lignin, hardwood, softwood, veneer; Grade Level: sixth through ninth grade; Total Time Required: 50 minutes (one class period); Setting: classroom
Goals for the Lesson
- Students will understand the makeup of wood.
- Students will be able to name several uses of wood from PA's forests.
- Students will develop an appreciation for the importance of wood in our everyday lives.
Materials Needed
- "Wood and Its Uses" worksheet, one copy per student
- chalkboard or overhead
- examples of products using wood
State Standards Addressed: E and E Standards: Renewable and Nonrenewable Resources (4.2); Agriculture and Society (4.4)
Subjects Covered: agronomy, social studies, forestry
Topics Covered: wood use in PA and U.S., wood chemistry,
Preparation
Read over the lesson and make sure you are familiar with the makeup of wood and its many uses. Ahead of time, assemble a variety of products (or product containers) that use wood products. Some examples include furniture, books, ice cream, cellulose sponges, toothbrushes, rayon fabric, and lumber. You will need these as visual aids for the lesson.
Introduction
"Wood is a nonrenewable resource that we use in hundreds and even thousands of ways. It is very much a part of our everyday lives in more ways than we realize. Today we are going to look at the makeup of wood and then at many of the products that include wood as an ingredient."
Steps
- Have the students come up with as many specific products that use wood as they can and put them up on the board. This will get them involved and hopefully generate some enthusiasm about wood and its many uses. Keep the uses on the board for later on in the lesson. This may take up to 10 minutes. When you feel you have enough, or students run out of uses, stress the extensiveness of the list and therefore the importance of wood in our lives. Tell them you will be coming back to uses later in the lesson. Where would we be without wood?
- Pass out the worksheets and begin filling them in with the students. Use the board or an overhead. Wood is the hard, fibrous, inner part of a tree. Wood is basically made up of five substances. Cellulose and hemicellulose are the fibers in wood and lignin is the glue that binds these fibers together. The other two substances make up only 3 percent of wood and are ash-forming minerals and "extractive" chemicals. The minerals are simply the minerals that were taken up from the soil by the tree. The "extractive" chemicals, finally, are the waste products that were given off by the cells when they were living.
- Briefly review the rest of the worksheet with the class. Go over the categories with the students to be sure they understand what they are.
- Have the students use the list of uses that they made up at the beginning of the period and have them insert them under the appropriate categories on their worksheets. You may also do this together as a group. Following are some wood chemical products and uses that students may not have come up with on their own: camera film, tires, ice cream, salad dressings, toothbrushes, toothpaste, turpentine, rosin. These are the product examples to bring in ahead of time and use at this time.
Conclusion
As you can see, we would be lost without wood and wood products. Not only do we use wood in its whole form, but we also use the substances that make up wood to make countless products for our everyday use.
Evaluation
Written exam
References
Georgia-Pacific Corporation (1999). "From the Forest."
Smith, Sanford S., and Lee R. Stover (2002). From the Woods: Incredible Wood . University Park, Pa.: The Pennsylvania State University.
Smith, Sanford S., Roy Adams, and Anni Davenport (2000). From the Woods: Hardwood Lumber . University Park, Pa.: The Pennsylvania State University.
Author
James I. Over, Northern Bedford High School/ Agriculture