My Cars Colour Changers

In the holidays last week I got 6 colour changers cars from The Warehouse in Newmarket along with 2 die cast cars and they are Lightning McQueen, Brand New Mater, Sally, Ramone, Sheriff and Boost. I put cold water to change the colour and warm water to change it back. I done 2 new tricks with the colour changers and first I put these cars in the fridge to change the colours then I use the hairdryer to change them back and it's called a science experiment.