Creating A Model For Seed Dispersal
Lesson 7 of 17
Objective: SWBAT design a system to spread seeds around the classroom
Students have been using I Can Statements all year to frame the goals of a lesson. Today I ask them to read the statement to themselves.I have posted, "I can design a model to move seeds from one part of the room to another."
I ask students, "What is a model?" (This is a review of previous lessons where students have built models of things such as the playground or a mountain. I am asking them to connect to prior knowledge before we begin the lesson. If they do not remember what a model is, I would want to go back and help them to draw from prior experiences by showing them pictures of models we have built, before proceeding with the lesson.)
When I am sure that students remember what a model is I ask, "Why do scientists use models?" Again students are connecting to prior knowledge about how scientists use models to help them look at different things that might be too big or too small to look at in their actual size.
I let students explain their thinking about models and why they are used before beginning the next part of the lesson.
Setting the Scene
Before the lesson begins, I place several paper flowers that I made around the room. With students watching from their seats, I walk around the room and shake the pretend flowers while dropping seeds from the flower on the floor or counters near the flowers.
When I am done I ask students, "What do you notice about the seeds from these flowers?" (They have fallen from the flowers. The flowers dropped their seeds, etc.) "When you walk through the woods, or around your yard at home have you ever seen flowers grow where no one planted them?" If students can not think of any, I ask about dandelions in the lawn. "Do people plant dandelions? How do they get all over the lawn?"
We talk about possible ways that the dandelions might spread, such as wind, kids blowing the seeds, etc. I ask, "Do you think animals ever help with the spreading of seeds?" "How might they do that?" I listen to student responses to see if they recall our previous lesson with the seeds and the piece of fur. I also listen for their own experiences that might help them think about how animals might spread seeds such as a dog coming home covered with burrs from a run in the field.
"Today we are going to make a model, sort of like a animal robot, that could spread the seeds from where they fell from the flowers, to other places in the room. You will work with a buddy wheel partner to design a model that you will then demonstrate for us. Your model needs to work without you touching the "animal" or the seeds with your hands. You can pull or push your model in some way (such as a string or handle), but you can't actually carry your animal from the plant to a new place in the room."
"I will call out your buddy wheel number and then you will plan out your idea before you come up and choose your materials. Remember you are making a model of an animal that could spread seeds from a plant to a new location. Talk to your partner about how you might want to make your model, sketch your idea and then come and take the materials you will need. I can cut the fabric into pieces if you want some."
I check for student understanding of the directions before proceeding.
I place recycle materials on the table, including furry fabric, felt, feathers, paper plates, paper cups, pipe cleaners, string, yarn, popsicle sticks, etc. I call out a buddy wheel number and students quickly find their partners, discuss their plans and come to choose their materials. As students come up check with them to make sure that they have a plan for their model before getting to work.
Building Our Models
I give students about 25 minutes to build their models. I provide them with a few seeds to use to test their models. During this time I walk around the room asking questions of the partners and helping them to think about what their model should be able to do (transport seeds without them physically moving the seeds or carrying the model from place to place).
I want them to think about how it is not enough for an animal to pick up the seeds. He/she must also be able to transport them from one place to another.
Sharing Our Models
When all of the groups have finished their work with their models I say, "Please return to your seats and would the partner with the name closest to the end of the alphabet please put the model on your desk until it is your turn. We will have one group at a time try to move seeds from one of the plants to another part of the room at least 3 feet (1 yardstick) away without touching the seeds with their hands, feet or breath."
Once all of the children are seated I ask one group at a time to demonstrate their model for us. We all watch how the model moves seeds from one spot to another. I ask each group to explain how their model works. Testing Out Our Models
I want to give students a chance to bring closure to the idea that seeds can be transported several ways. I ask them to look at the I Can Statement and to give a thumbs up if they created a model that moved seeds. If their model was unsuccessful I ask them to give themselves a thumbs up for attempting to build the model if they felt that they worked hard on it. I remind them that not everything a scientist models works the first time.
I close by asking students to tell what they noticed as they built and tested their own models and looked at the models of others.
I use this discussion to gauge the class understanding of the process of transporting seeds in nature.