The first one was the short one. Does yeast produce gas as a waste product when growing (or just produce gas when growing)? He cleaned up several pop bottles, put some warm water, a little sugar and a packet of dry yeast in a couple of them. Stir them up! He did one bottle (or you can do more than one) with nothing in it as a control. Then he stretched a balloon over the top of each bottle. Get your camera ready. It doesn’t take long for the balloon to start inflating over the bottle with the yeast growing in it proving the yeast does produce a gas. You can then do research on the net about why and what gas, etc.

The second one was also about a gas, but took longer. The question asked was, do fruits, when placed near each other, cause faster ripening? You will need gallon ziplock bags, at least 3 different kinds of fruits that change color when ripe (we used bananas, pears, and tomatoes). For one bag, place one of each fruit in one bag together. That’s the one to prove your experiment. Have another bag for each single one of the other fruits. Those are your controls. Zip them up tight! Again, a camera is needed to show the progression of ripening. After a couple of weeks, you can clearly see the fruits that were together ripen faster. You have to do the best you can to buy fruits that are about the same ripeness (or un-ripeness). And again, you can do research on why and what.

They both make good displays because the pictures will be colorful and if you need to take it to school, You have hands-on displays to show. My son got top scores on both.