Today we did an round of observations suggested by NASA’s Space Can Be a Chilly Place lesson plans.
The second activity in this lesson plan packet involves observing four different blocks of ice: plain water, water with some blue food dye mixed in, water with salt added, and water with some soil added. I didn’t particularly plan ahead for this activity so I went out to our recycling bin last night to look for some plastic bottles that I could use. I filled up each container according to the directions in the lesson plans, making sure not to fill the bottle completely, and I stuck them in the freezer overnight.
Today I cut apart the bottles to free the blocks of ice and I put each on its own plate. I had my daughter bring her science notebook and record her observations as well as draw a few pictures of what she saw. First I asked her to touch the ice to see if they all felt the same and she replied that all were very cold and most were smooth except for the one that was made of frozen salt water (it was crumbly according to her). I then had her smell the ice to see if she detected anything and she said there was no smell. Finally, we talked about what each block of ice looked like. I also brought out a flashlight so that we could highlight the structures seen inside the blocks.
Towards the end of our observation session my daughter remarked that the salt water block was melting much faster than the other three. This led towards a discussion of why salt is applied to roads in the snowy north.
If your child has never had the opportunity to look at big blocks of ice before, then this is an easy lesson to set up. I would suggest using large paper cups to freeze water in, if possible, so that the cups may be easily torn away….cutting the plastic bottles was not much fun.
Activity 4 in the same lesson plan has four short pages about ice in our solar system and why it is important to study ice. These quick pages wrap up the observation activity rather well I think.