The MiniMads played with ice treasures I had frozen earlier this afternoon. It is a great idea that I borrowed from a friend. I froze small items eg plastic dino's, bugs and beads in layers in a bowl and then let them lose with salt toothbrushes and spray bottles filled with coloured warm water. It is especially great when the weather is warm. You could always do smaller ones in ice cube trays or weaning pots, which would take less melting and put the whole cube in a bowl of warm water.