Grace and Jack loved, loved, loved making a microbial biosphere - which is a self-contained ecosystem in a jar. We talked about how microbes are living creatures that are so small that you can't see them without a microscope, but if enough of them grow together you can see their 'community.' We also talked about how microbes can make us sick (and then we call them germs) but more often they help us! Microbes break down plants and turn them into compost and the microbes in our intestines…