We've been busy making whirligig, helicopter type things this evening (click here, for the printable template from ThinkingFountain.org), to reinforce the concept of how seeds travel on the wind.
We actually started out reading The Dandelion Seed by Joseph Anthony, following the fictitious journey of one lonely dandelion seed. But our dandelions have not gone to seed yet, and we don't usually encourage the children to blow them around the yard, anyway. So, instead we settled with making paper helicopters, weighted down with paper clip "seeds", and compared them to the twirling motion of a couple of maple seeds we found outside the library.
They flew almost exactly the same. In fact, there was quite a bit of excitement, when the wind picked up, and started to carry the helicopter born paper clips aways, just like real seeds.
It's great to be a homeschooler.