Keywords: Leaf/Tree Identification, Terminology, Dichotomy Key; Grade Level: 3rd grade; Total Time Required: for review and game, approximately 50 minutes and Depends on students understanding of concepts, might be best to do over two days or more; Setting: Classroom
Subject Covered: Science/Environmental Education
Topics Covered: Leaf Identification, Terminology, Dichotomy Key
Goals for the lesson: To be able to understand terminology, identify leaf characteristics.
Materials Needed
Dichotomy key, 8 sample leaves (see below), bingo cards, markers, calling cards, tree identification book
State Standards Addressed:
Environment & Ecology 4.2.4 A/ B/C/ D, 4.3.4 A/B, 4.8.4A/ B/ D
Teaching Model Used: Hands-on
Methods
Pre-Assessment: Students have previously been introduced to unit on Trees/ Natural Resources and have talked about the importance of trees and uses of trees. Now we are moving on to tree identification. This particular lesson covers just tree ID but should be used as part of a large unit.
Set Induction: Students will be shown a variety of different types of leaves. One representing each of the leaf arrangements (Alternate, Opposite, Whorled) and ones that show the different leaf types (Simple, Pinnatelly Compound, Palmately Compound, Needles). See below for suggested leaf types. Have students discuss the different characteristics of each. What is similar? What's different? Record their brain storming on a chart to be hung up in the room.
Procedure
Preferably in small groups…
Other students could get started on the next lesson - Leaf Booklets, see lesson plan #2.
1. Identify the various parts of a leaf: Bud, Petiole, Midrib, Blade or Leaf on a simple leaf and a compound leaf. Illustrate the various parts of the leaf on a chalk board, provide samples for students to inspect and/or photographs to examine.
2. Identify the following terminology and show examples using applicable leaves.
- needle
-alternate
-opposite
-whorled
-simple
-compound
-margins (entire, lobed)
This can be tricky to learn and hard to remember. Provide multiple examples. Once you feel the students are grasping this, move on to game.
Closure: To help review the various characteristics of a leaf, play Leaf Bingo. Instructions: Using the reproducible page provided, make enough copies for each student in your class. Then have students cut out each square and glue them on a piece a paper, making a 3x3 board. Stress the importance of variety so that no two boards look the same. Each student (or students can work together in groups of two), receives one game board and a cup full of markers. The caller (Teacher) uses the stack of calling cards (see attached) to call out a characteristic. If a student has that characteristic pictured on their board, they mark the spot with a chip, as you would do in Bingo. When a student gets three in a row, they call out Bingo and together with the teacher they check to see if their cards match the characteristics given. Repeat play. It may be easier for students to work together with a partner at first, then playing independently as they become better at identification.
Follow-up: (2 Parts - first part should be done before students learn too much about trees. The second part should be done later.) Ask students to find trees (at least 4) in books provided that they believe are located around their homes. Each student makes a list of those trees and then brings in a sample leaf from each tree. Students will then utilize the information they have learned, as well as the books provided to determine if they were correct in their initial guesses. Students could make a leaf booklet if so desired, which not only identifies the different types of leaves but the various characteristics as well.
Follow-up: Teach students how to use the Dichotomy Key, building on the information they have just been taught.
The following leaves are only a suggestion and provide a good variety of characteristics for this lesson. Many of the leaves will fall into more than one category such as simple leaves with lobed margins.
Sample Leaves:
White Pine (Needles)
Red Oak (Sharp pointed lobes)
White Oak (Rounded lobes)
Horse Chestnut (Palmately-compound)
Black Walnut (Pinnately-compound)
Birch (Simple)
Dogwood (Opposite)
Evaluation
Students will be evaluated on their participation and completion of lesson #2.
Sources Cited
Summer Key for Pennsylvania Trees, Pennsylvania State University, College of Agricultural Sciences, Cooperative Extension
Author
Kelly Garthwaite, State College Friends School
