How to Make Seed Dispersal Hands-On

Once upon a time, our third graders planted seeds every spring and we watched the Brassica plant change through its entire lifecycle- including pollinating them with dried bees. This was always my favorite day of the year!

I would hint to my third graders that the "bees were coming" and they just assumed the bees were alive. On Bee Day I would have my door closed and a note on it saying to be quiet because the bees had arrived.

They would come in whispering and looking around for the bees. Later I would bring out the dried bees. I loved it! Fooled them every time.

So, how can we add some of this excitement to the STEM Lab....hmmmm.....
STEM Challenge- students design a model of one of the ways seeds are dispersed. Each group is assigned one of the methods and then must determine which of the materials can be used to best build a model. They must choose their materials wisely to gather exactly what is needed to build the model. Finally, the teams will share their creation and demonstrate how it works. Students will be incredibly creative in finding a way to disperse the seeds and will love sharing their final product.

A Little Background

What if we could learn more about seed dispersal after the seeds have been created in the plant? BAM! This challenge was born!

I drew a fabulous anchor chart showing the methods of seed dispersal and we had a great discussion including ideas of how we could build something for each method.  

STEM Challenge- students design a model of one of the ways seeds are dispersed. Each group is assigned one of the methods and then must determine which of the materials can be used to best build a model. They must choose their materials wisely to gather exactly what is needed to build the model. Finally, the teams will share their creation and demonstrate how it works. Students will be incredibly creative in finding a way to disperse the seeds and will love sharing their final product.
I mean, seriously, it's a great anchor chart. I am not one bit artistic, but I can look at photos and sketch a little and colored pencils create the rest.

After our discussion, we also watched several short videos about dispersal. Then I passed out the assignment cards. I chose six different dispersal methods (the ones I thought we could actually recreate as a STEM project). Each group had a different assignment card. Then they had some decisions to make!

How would they build a model and what materials would they need? I created a list of materials and they could choose what was needed for the dispersal method they were designing. This turned out to be challenging!

Dispersal by Animals and Wind

ANIMAL DISPERSAL - Basically, animals move seeds by eating the fruit of a plant and then expelling the seeds. They might also move seeds by taking the seeds back to the homes. Kids really enjoyed thinking about this one- mostly because they like to say the word 'poop'! The cute little bird is made of tissue paper and craft sticks. The group explained that the bird had seeds in its mouth and after eating he would poop them out!
STEM Challenge- students design a model of one of the ways seeds are dispersed. Each group is assigned one of the methods and then must determine which of the materials can be used to best build a model. They must choose their materials wisely to gather exactly what is needed to build the model. Finally, the teams will share their creation and demonstrate how it works. Students will be incredibly creative in finding a way to disperse the seeds and will love sharing their final product.
WIND DISPERSAL - Lightweight seeds pods will blow in the wind and my groups had a blast designing parachutes for this one. The team in the above photo made a "sled" that blew because of the sail they attached. They blew on it and as it moved forward the seeds were supposed to fall off.

Dispersal by Gravity and Attachment 

GRAVITY DISPERSAL - Gravity is a form of dispersal, but generally results in dropping the seeds right near the parent plant. This is really not what you want to happen. So, teams were challenged with dropping the seeds, but maybe moving them away from the plant, too. Some tried a bouncing method for this or a balloon that exploded. Some just had the seeds drop straight down. The trees below worked really well. On the right, you can see the hanging fruit that is ready to fall.

STEM Challenge- students design a model of one of the ways seeds are dispersed. Each group is assigned one of the methods and then must determine which of the materials can be used to best build a model. They must choose their materials wisely to gather exactly what is needed to build the model. Finally, the teams will share their creation and demonstrate how it works. Students will be incredibly creative in finding a way to disperse the seeds and will love sharing their final product.
ATTACHMENT DISPERSAL - Attachment is the dispersal method that involves plant parts clinging to an animal. This one has an interesting story that involves the invention of velcro! We watched a short video about velcro and that helped kids understand how to make a model of this form. The photo above is showing a dog with seeds clinging to his "cotton ball" fur!

Dispersal by Water and Explosion

WATER DISPERSAL - Did you know that most seeds float? So, what would you build to show this dispersal method? Most of my groups built a form of a boat that carried the seeds away. The one in the photo floated and held the seeds and the team explained that rough water would make the seeds pop out.

STEM Challenge- students design a model of one of the ways seeds are dispersed. Each group is assigned one of the methods and then must determine which of the materials can be used to best build a model. They must choose their materials wisely to gather exactly what is needed to build the model. Finally, the teams will share their creation and demonstrate how it works. Students will be incredibly creative in finding a way to disperse the seeds and will love sharing their final product.
EXPLOSION DISPERSAL - This dispersal method was, by far, the one all the kids wanted. They just loved thinking about placing seeds inside a balloon and then popping the balloon to create the exploding and seed dispersal. We had a lot of fun watching the testing of those seed filled balloons. Every single time a balloon popped someone would scream!


Did We Have Problems with This one?

Of course! We always have things happen that create problems to solve- or funny things to happen! Take a look!

This team above made a boat of cotton balls. They were truly perplexed when it sank very quickly. This STEM Challenge was all about choosing the right materials to build a model!

Above- a team picked a balloon as the building material for their boat. Well, of course, it floated. But was this the best choice for a building item? Absolutely not! The seeds placed on top of the boat made the boat twist with that added weight and turn over. It was not what they expected.

Above - I had these little gloves from the Dollar Tree that had a very stringy and coarse texture. I thought they would be great for making the attachment model, but the team wanted it to make an animal model. They created the animal above which we thought was a bird. They declared it was an insect and it does look like a winged insect. Was the glove the best choice?

Parachutes are fun to make and kids love trying them. Above the team made a tiny parachute and the weight of the cup made it crash to the ground. It did scatter the seeds, though.

And, finally, the above model. This one was puzzling for me and I could not decide what the team had built. It's a mess, I thought. Ah, but you should never underestimate kids! Here's the explanation:
"It's a dog. When you put a seed inside the white cup on the left it will travel all the way through and come out the other end. Why can't you see the dog's head? Because that dog has just been to the vet and it's wearing a cone!"

You have to admit that is really funny!

You need to try this challenge! It is such a fabulous learning experience!


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