Keywords: simple and compound leaves, hard and soft wood trees, leaf margins; Grade Level: pre-K, 3-5 year olds; Total Time Required: 30 minutes; Setting: Classroom, outdoors

Subjects Covered: Mathematical Thinking & Expression, Scientific Thinking & Technology

Topics Covered:
* Leaves come in a variety of shapes.
* Needle shaped leaves come from trees that have cones (soft wood).
* Leaves that are broad and flat come from trees that lose their leaves in the fall (hard wood trees).
* Leaves can also be described as simple (one whole leaf) or compound (made up of smaller leaflets) in shape.
* The edges of leaves also have different shapes.
* Trees use their leaves to make food to help them grow.

Goals for the Lesson

* Children will observe leaves from trees growing on our CDL school playground, and at the site of our new facility currently under construction in the Hort Woods.
* Children will use simple tools to observe leaves that have fallen (with magnifying lenses) and those still growing on trees (using binoculars and digital cameras).
* Children will understand that it is important to observe leaves without picking them because trees need leaves to make food.
* Children will sort leaves by a variety of attributes--needles vs. broad leaf shapes; simple vs. compound leaf shapes; shapes of leaf margins.

Materials Needed

* Magnifiers, binoculars, and digital cameras.
* "The World's Largest Plants; A Book About Trees" by Susan Blackaby.
* "Summer Key for Pennsylvania Trees" http://sfr.psu.edu/youth/sftrc/lesson-plans/lesson-plan-pdfs/summer-key by Sanford, Smith et. al.
* Fandex Family Field Guide: "Trees Identified by Leaf, Bark & Seed" by Steven M.L. Aronson

State Standards Addressed:
PA Learning Standards for Early Childhood - Pre-Kindergarten (2009)
Mathematical Thinking & Expression:

  • Determine the attributes of shapes
  • Group objects according to common properties
  • Sort objects by two or more attributes

Scientific Thinking & Technology:

  • Use the five senses as tools with which to observe, classify, collect information and describe observations

Teaching Model: Hands on learning and student inquiry

Methods

Activity 1. - Introducing the Lesson. (5 minutes)
Ask the children to identify simple shapes. Have children assist in sorting a basket of familiar materials such as blocks by one or more attributes--such as color, size and shape. Explain that we can also sort leaves by their shapes in several different ways.

Activity 2. - Vocabulary and Examples. (10 minutes)
Read "The World's Largest Plants: A Book About Trees", emphasizing the ideas listed above. Show children examples of each of these leaf types and shapes, as well as simple and compound leaves, using "Fandex Family Field Guides: North American Trees Identified by Leaf Bark & Seed". This guide is colorful, with individual photos that are die-cut to retain the leaf shapes, and are on cards that may be separated from one another for easy sorting.

Activity 3. Playground Observation.
(15 minutes)
Observe leaves on our current playground which has 5 species of trees. See if the children can recognize the attributes discussed in the previous activity and find the trees/leaves on our playground that match the examples from the field guide. Model use of vocabulary from previous activity--needles, flat leaves, simple and compound leaves. For children who can easily sort by these categories, introduce the idea of observing, describing and categorizing leaf edges (margins). Use simplified vocabulary to differentiate these shapes--entire=whole, lobed=curved, serrate=pointed, and dentate=teeth-bites.

Additional Activities to Extend Student Learning
Observe leaves at our new building site in the Hort Woods. Compare the number and variety of leaf shapes and trees in each location. Make leaf rubbings of fallen leaves.

Evaluation (5 minutes)

Using individual photos/leaf shapes from the Fandex field guide, give individual children opportunity to sort them into the following categories:
* broad flat leaves vs. needles
* simple leaves vs. those with leaflets
* leaf edges that are whole, curved, pointed or have teeth bites

Literature/Sources Cited

Aronson, Steven, M. L., Fandex Family Field Guides: North American Trees Identified by Leaf, Bark & Seed. New York, Workman Publishing Co. (1997).

Blackaby, Susan, The World's Largest Plants: A Book About Trees., Picture Window Books, (2003).

Smith, Sanford, S., Brohn, Paul, Rader, Terry, D., and Grippo, James, J., Summer Key for Pennsylvania Trees., Pennsylvania State College of Agricultural Sciences, (2002).

Author

Misty Woods, Penn State Child Development Laboratory/Preschool