If you have not tried this, you must.
Two parts corn starch to one part water. Mix. And let the weird ooey-gooeyness begin!
It is a crumbly-like substance.
But, wait! Now it is a drippy liquid.
And, even though it looks like a huge mess (which some how makes it seem more fun) when it dries, it just sweep right up.
Easy-peasy and hours of fun!