Our 4rd graders at the secondary school have become straightforward scientists and they decide to catch all the tiny living things, which are around us. As the students said: “there are so many bacteria and fungi in the air we are breathing and in all the stuff we are constantly touching, so we are going to prove it”.
https://yourfuntasticworld.wordpress.com/2018/11/15/microbes-we-cant-see-them-but-they-are-around-us/