Introduction
Students will begin their investigation of trees by:

1. Brainstorming their existing knowledge of trees.
2. Developing criteria for tree identification.
3. Doing a simple school site tree inventory.

Questions

1. What do students already know about trees?
2. What criteria do we use to identify trees?
3. How many trees do we have on our school grounds?

Materials
Classification worksheet

Procedures

1. Begin by asking students what they already know about trees. This can be done using the K,W,L method (Know-Want to know-Learned), webbing, concept mapping, or any other brainstorming technique. Use this to introduce the unit and begin a discussion of what the students think they will be studying.
2. Have students cut out the shapes from the classification worksheet and then classify the objects according to a system of their choice. Write some of these on the board. Discuss the different systems. Encourage them to come up with even newer ones. Discuss the attributes of the objects (size, shape, pattern). From this discussion, ask students to list the attributes of trees (leaves, bark, buds, shape, etc.).
3. Go outside and walk the perimeter of the school grounds and note the trees there. You could simply count how many there are, or start to make a map with each tree. You could note shapes and how they are different, or compare natural areas to landscaped areas if you have both. The extent of your school inventory is up to you depending on student interest, time, etc.

Discussion Questions
Questions which come up at this time are great for research and for further discussions. Some you might expect:

1. Is this a tree or a bush?
2. What kind of tree is this?
3. How old is this tree?
4. How could we count the rings without cutting it down?

Blowouts

1. Expand the classification activity to teach the scientific naming system of Kingdom, Phylum, Class, Order, Family, Genus and Species.

Cut out the shapes and arrange them into groups which go together. Is there more than one way to arrange them? How many different ways can you think of?