My boy spent literally hours creating his.
To make fill a bucket with water and freeze. For best results 2-3 days in the freezer. Overnight will work but result in a pocket of water. Then again reaching the pocket of water was great fun. Once you have a block of ice transfer it to a cake pan, fill a water bottle with warm water and salt and let them squirt away. Warning: You may go through a box of salt depending on your child's interest. The effect is really cool.
Squirting in the same spot results in tunneling. Cool stuff.
Yesterday we arrived home to a Sear's truck in the road. Turns out one of our neighbors got a new washer and dryer. DS went up to the Sear's man and asked if he could have the washer box. Below is my son creating his fort/pirate ship/ club house.
Today he spent his own money on two cans of spray paint. Of course one being his favorite color...ORANGE!
So how long does it take spray paint to come off hands?
A boy and his projects...priceless.
