Ready for another food model? I love using anything edible to demonstrate science concepts whenever I can, and this week seemed to be full of food activities! Recently, in my 7th grade class, we have been studying the integumentary system. This includes the layers of the skin as well as the “stuff” inside.
We had discussed the different parts of the integumentary system in a previous lesson. Students used a diagram to label each layer and write down the function and purpose.
I did throw in one little demo that shows how oil affects our skin. The oil glands secrete oil that helps provide a barrier for our skin. First, I had students use an eyedropper to place a drop of water on their skin. We noted how the water stuck together. Then I took a cotton ball and swabbed their other hand with rubbing alcohol before putting on another drop of water. This time, the water droplet ran right off — it did not stay stuck together. The rubbing alcohol had taken some of the oil of the skin and in doing so, the skin was not as water resistant!
My students did like that demo, but obviously the food part was a bigger hit! I originally found this activity here at My Mundane & Miraculous Life and couldn’t resist trying it.
Here are the materials needed to make the jello skin model:
- 4 packs of Jello (I think orange works best so you can see the inside)
- Mini Marshmallows
- Fruit Roll Up or Fruit by the Foot or another type of fruit leather
- Twizzler Pull n’ Peel
- Make the jello but use the “Jiggler” recipe. (I think it uses less water and makes a firmer Jello. If you aren’t using Jell-O brand, you can find a jiggler recipe here)
- Let the jello set for a few minutes (until it isn’t super hot) and pour the marshmallows on top. Then let it set for at least 3 hours or overnight.
- Cut the jello in pieces and place the pieces on a plate upside down so the marshmallow layer is on the bottom. Each student gets a piece.
- Have the Twizzler Pull ‘N’ Peel and cut into sections and the Fruit Roll Up unwrapped and ready to give to each student
As a class, we discussed what two layers of the integumentary system the model represented so far (marshmallows= fatty tissue or hypodermis and the jello = dermis)
Students then received a piece of Fruit by the Foot (but other materials would also work) to put over their jello. This represented the epidermis.
Students received pieces of Twizzler Pull N’ Peel. Some pieces were used as hairs. Students had to poke holes in their epidermis and stick the pieces in. Other pieces could be rolled up and stuck inside the dermis layer to represent sweat glands. I used plain red Pull ‘N Peel, but it would be neat to try multi-colored (I’m pretty sure that exists…) and each color could represent something else in the skin: hair, sweat glands, nerve receptors, etc.
I’ve heard of also using things like chocolate chips to represent moles on the skin surface. Creative!
The best part is, after students have completed their model, they can eat it! Delicious!