I'm using the next few minutes to wriggle my fingers in the internet to feel out for a chemistry set for our two girls of 8.

Any recommendations?

caffeine extraction?

well caffeine could be easily extracted from black tea.
just simmer black tea in water for 5 minutes, then add some sodium carbonate and extract with DCM.
it works

Most chemistry sets today are so watered down as to be unlikely to hold a child's interest.

Try the following book for better ideas:

Illustrated Guide to Home Chemistry Experiments by Robert Bruce Thompson. Available on Amazon for $20.

elphologist

I dont know about ready chemistry sets, though I remember having one as a kid that was quite fun...

but anyways when I read elphologist's post it reminded me of this ebook I have, let me post here it might interest you

its a very nice illustrated book called "The Golden Book of Chemistry Experiments: How to set up a home laboratory - over 200 simple experiments"

Look up acetameniphen synthesis.

It's a fairly simple experiment (you need a bunsen burner & supplies) but completely legal, and you made your first drug! Good job kids!

But they are 8 huh?

Yeah, like someone else said, it's not the 60's or 70's anymore -- chem sets are bland & lame now.

thanks for the feedback! and the books D:

Kids love big coloured crystals.

yeah, try growing CuSO4 or potassium dichromate crystals.
it's very easy and the xtals look beautiful!

that's definitely one of the things i want to do! woot woot!