Year 3 and 4 pupils create tiny worlds in preserving jars. Layer by layer, they add gravel, soil, moss and plants – including tiny creepy-crawlies. Over time, fascinating things happens: Drops of water form on the glass lid, rain down and water the plants. The grass begins to grow and a creepy-crawly gets hungry, much to the chagrin of the clover. And there are many other things to discover. – An ecosystem – with all its surprises and challenges.