Bacteria are tiny microorganisms that are too small for us to see – on their own. If we can grow a big group of bacteria, we can see them. To grow a lot of bacteria, we need to prepare a food they like to eat. Scientists call this food ‘nutrient agar’, or just ‘agar’. Agar is a jelly-like substance. In this activity, you can make your own homemade agar, and use it to grow bacteria you have collected from different places around your house. Scientists who do this kind of work are called microbiologists.

Try our free experiment:

Grow Bacteria on Homemade Agar Plates