Test some simple structures for their surprising strength.
See if you can make a flimsy piece of paper strong enough to hold up a lot of weight.
Experiment with a mini windstorm to see if your building will stay standing.
Make your own air pressure lifter and see how much weight it can lift.
Make a spaghetti strength tester to see if more spaghetti can hold more weight.
Find out which wrapping material can make an ice cube last the longest.
Use heat and a chemical change to make a soft substance hard.
See which kind of tape can handle the most weight.
Create a stickiness tester and try it on some of your favorite sticky foods.
Be a glue scientist and invent the stickiest glue.
Test materials to see which makes the best flyer.
Test different mixtures to come up with the hardest plaster.