The James Dyson Foundation has designed a set of 44 challenges related to science & engineering specifically for kids (ages 7 & older), which are perfect for these at-home learning times. The challenges include making an air-powered car out of a balloon, strong bridges out of spaghetti, and a cardboard chair strong enough to hold a person:
Here's the PDF with all 44 challenges. What I like about these projects is that they're hands-on, you can do them with stuff you already have around the house, and they're educational in the best way: there's no "teaching" really...the challenges are designed to appeal to the natural curiosity of kids.
Reading through these, the one that blew my mind was that you can determine the speed of light by melting a chocolate bar in the microwave.
That's so cool! (via open culture)