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Nothing is grosser than pitri dish bacteria, but when you make it with jello and candy it becomes both gross and delicious! Perfect for a Halloween party or simply for Halloween science experiments!
Edible Pitri Dish Bacteria STEM Activity
We did this fun STEM activity on a whim to see if we could re-create bacteria cultures growing in an ager using edible ingredients. The kids were aptly disgusted and delighted by the combo we came up with. These would make adorable little party favors for a Halloween party or a mad scientist party!
What You’ll Need to Make Your Own Edible Pitri Dish Bacteria
Cook your jello according to the package directions. You can make it the regular way or the “jiggler” way. We actually made our own using food coloring, sugar, and some unflavored gelatin powder, which set up much quicker than standard jello.
After the jello dissolves and cools a bit, pour it into your (clean) pitri dishes. Let it set up for about an hour. We stuck ours inside a casserole dish for easier transport.
When the jello starts to set up, add your candies to make your bacteria. We modeled ours after real bacteria shapes seen in a microscope (which you can see in the picture below). We didn’t do spirochete because we didn’t have any candies that looked like that. But if you had Twizzlers, fondant, or something like that, you could easily make this shape. For mold, we sprinkled sugar on the jello. This eventually melted, but the pattern continued to look moldy.
Return the pitri dishes back to the fridge and let the jello harden completely. The candies will soften and give the candy a feathered look, which looks even more bacteria-like.
Discuss the different shapes bacteria can have while you eat this delicious snack! We are absolutely going to make these at our next scientist-themed party. They would also be perfect for Halloween party snacks!
More Halloween Science and STEM Activities
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