Holes and cracks in the floor are no fun, but the fix is pretty simple. Just stick a crayon in the microwave.Photo by Chris Metcalf
Actually, there's a little more to it than that. The Guardian has the details:
Crayons make an excellent filler for small gouges or holes in resilient flooring. Select a colour that closely matches the floor. Melt the crayon in the microwave on medium power over a piece of greaseproof paper, until you have a pliant glob of colour. With a plastic or putty knife, fill the hole. You can use a softened crayon to cover even quite deep scratches on wooden furniture.
Considering your kids are probably the ones gouging the floor in the first place, melting one of their crayons to fix it not only solves the problem of the hole in the floor but also allows you to punish the culprit as well. Nice.
An A-Z of incredible uses for everyday things [The Guardian]