One of our favorite things is experimenting with seeds. Just before the last lock down we created a house made of sponges added some mustard seeds and a wee bit of water and watched what happened. The seeds at the bottom of the sponge house grew better than the ones at the top.
We also had two potatoes and a kumara suspended above a jar of water to see if they grew any roots, and to our surprise one of the potatoes did. So, during the last level 3 restrictions we planted them in the garden to see if they will grow, will let you know later.