I invite students to read the I Can statement with me to begin the lesson. We read, "I can identify patterns in different parts of plants." I ask students , "Have you ever looked at a plant from the eyes of a scientist? What do you think you would notice if you really looked at a plant?"
I know that students have all seen many different plants, but have they taken a plant apart, studied how it is made and identified any patterns that they see in a single plant or across plants. The purpose of this lesson is to give students a chance to identify similarities across several different types of plants and to realize how the patterns of growth are repeated across different plant species. The Next Generation Science Standards identify patterns as a crosscutting concept that all students should be aware of.
I invite students to come to the rug to begin this lesson.
I have collected a variety of different plants for this lesson. I have collected leaves, stems, roots and complete plants. (Depending on the season and where you live, it may be possible to have students go out and collect the samples before beginning this lesson.)
I spread all of the plant parts on a large piece of paper on the rug. I say to students, "what do you see here?" (plants). "Are they all the same?" (no) "What is different about them? (different parts of the plant, there are roots and leaves and flowers and stems, different colors..) Are there any things that are the same? (lots of green, many leaves are pointed, stringy roots..)
"Today you are going to really look at the parts of the plant the way a scientist would. I am going to demonstrate how a scientist might look at a plant and record what he or she sees, and then you are going to have a turn with your own part." I choose one sample that is the most unique so that the children will be less likely to exactly copy what I have done. I take a plastic knife and gently cut open the stem. I use a magnifying glass to look at what is inside. I draw the open stem on my paper and label the stem and anything I see inside. I tape a piece of the stem to my paper. Next I look carefully at one leaf with the magnifying glass. I draw what I see and label the veins, and spots on the leaf. I gently cut into one part of the leaf and look again and label what I see. I count the points on the leaf and the veins and record that in my journal. I say, "Do you see how I have looked at my plant and drawn what I see? I have also cut it gently apart and recorded what is inside. I want you to do the same with the plant you get. You can tape parts onto your paper, draw and label what you see. Try to see if your plant has symmetry (the two sides are the same), see if there are an odd or even number of points, you could measure the length of the roots or the stem or the leaf but be sure to record all the different ways you look at your plant."
I ask for questions and then I hand each student a plant specimen, a magnifying glass, a plastic knife, and several sheets of plain paper. Journaling Our Findings I ask them to return to their seats to work.
I give students about 20 minutes to study their plants and record their work on their paper. I circulate around to ask questions and to hear what they have discovered.Studying the Plant
When students have finished recording their findings I ask if any student would like to tell us one thing he/she found. I allow students to share out what they discovered.
Next I say, "I want you to look for patterns among the plants we have studied. I am going to give you a number card. You will find the 3 other people on your plant team. You will bring your papers together and set them out so everyone in your group can see them. I want you to look for patterns, things that are the same and occur in the same way among the 3 plants you have studied. You should record those patterns on your papers by highlighting them on all 4 of the papers or at least 3 out of 4 papers. After about 10 minutes we will come together to see if there are any patterns that run through all of the plants we studied.
I hand out the cards and students quickly find their groups and begin to look for things that occur in at least 3 of the papers, such as all have leaves with 3 points, or all have stems that have 2 leaves growing off them. I move about listening to the discussions in each group.
When all the groups have finished finding patterns within their groups, I ask them to choose 1 person to share their findings with the rest of us and then for all groups to come sit together on the rug.
I let each group share the patterns they found. As each group shares 1 pattern I ask how many other groups found that pattern. I record the patterns on the easel.
When all groups have shared their patterns, I ask students to look at the kinds of patterns found in plants. I ask, "Why do you think that there are patterns in the way things grow in nature?" Here I am not looking for a specific answer, but rather for students to think scientifically and communicate their thoughts based on what we have discovered. I am looking for examples of logical thinking and reasoning in science.
I ask students to return to their seats. I say, "to finish up today, I would like you to write me a short paragraph where you tell about patterns in nature. Please make a decision about whether you think there are patterns in growing things. You can start your paragraph with "I think there are patterns in nature." or "I don't think there are patterns in nature." You will then need to write at least 2 good sentences to tell me why you decided what you did. You will need to end with a closing sentence. Don't forget that you want to write enough to convince me for or against patterns in nature."
I ask for one child to repeat the directions. I give students about 15 minutes to write their paragraphs. I encourage children who may have difficulty getting started by helping them decide whether to say there are or there are not patterns.
I collect the paragraphs to assess student ability to communicate scientifically, to use sound reasoning, and to support their belief about patterns in nature.