DD has an assignment of two evaporation experiments (salt water, observing how the salt doesn't evaporate with the water, and sugar water and food coloring, observing how the water leaves behind colored crystals). Of course we've done similar experiments years ago, and she's asking for something new. I'd like it to be related still. Anyone know of a good experiment or two where we could practice the scientific method and do something a bit more advanced? TIA!