OMG the champions exploded

Look at that...

This is how fast mushrooms grow, isn't it impressive?

I don't keep them in the window, it was just to get light enough to get a decent picture. 

Otherwise I keep them in a dark place.

I have a spray right next to it, just to make it handy to spray with tempered water each day.

I really hope you are able to get your hands on a mushroom kit. Kids love it, especially cause they grown so fast.
So have some fun with the little ones this way, they learn a lot from it too and gives birth to many funny conversations :-)