Experimenting with Hot/Cold:
If you have a block of ice or simply a few ice cubes stuck together, let your child/student touch and describe how the ice cubes feel. Then, put the ice cubes under hot water (make sure to have adult supervision so no child gets burnt), and watch how quickly they shrink and ultimately disappear! No matter how old you are, it's fascinating! This would also be a great opportunity to discuss solids and liquids!
Fill a cup with water and use a marker to mark where the top of the water is. Then, put the cup in the freezer until the water freezes. When removed, the water will have expanded when it turned into ice and will now be above the line!
Ice & Salt:
There's at least two ways to experiment with ice and salt. You can either have a block of ice and put salt on it to observe what happens, or you can fill two cups with water, and in one cup pour salt and mix. Place the two cups in the freezer and watch to see which one freezes first! These are great experiments to do especially in the Winter for young children to understand icy roads and why salt is placed on roads!