Hand out hand lenses for students to make more careful observations and begin to count rings. (What are the rings? Usually a few students know that the rings have something to do with the age of the tree) Add new vocabulary: cambium, xylem, phloem.
6. Students systematically count rings from bark to pith. Discuss counting techniques and the importance of replication of data and using similar methods for counting.
7. Students calculate the age of their tree sample (bark is considered present year for this activity). Using current year as start date, students will subtract to find age of tree.