My daughter seemed skeptical when Dad promised a fun day with science. She was hoping to watch Jimmy Neutron on Nickelodeon, but I assured her that the real thing would be more fun. By the end of the day, it was clear that I had convinced her.

Our first task for the day was to drop by a local store to pick up supplies: some drier ventilation tubing, insulating gloves, balloons and a Styrofoam cooler. The cooler would serve two purposes: as a place to store the dry ice on the way home, and as part of our "fog cannon." Our next stop was our local ice cream store where we purchased 2 pounds of dry ice. I also needed an old cardboard box, a chisel and a hammer, all of which I had in my basement workroom.

At home we set about making our fog cannon. We removed one side of the cardboard box and taped a plastic bag loosely over the open side. The seal around the bag must be air tight, but with enough "give" so that when you hit the bag it displaces a large amount of air quickly. We cut a small, circular hole in the other end of the box. Now it was time to "load" our cannon.

We needed to fill the box with C02 vapors. This was the first science lesson for my daughter: What is dry ice? Why is it called dry ice? We filled the cooler with warm water and placed a piece of dry ice in the water. It bubbled furiously, and at first she ran up the stairs and refused to come back in the room! I explained that Dad was a professional and knew what he was doing and finally managed to coax her back. She was amazed!

Why does it do that? What is the "smoke"? The day was already a success because I could see her mind at work! We managed to get the dry ice vapors into our cannon box. This proved tricky, and we needed to experiment a little, but that was what the day was all about! Eventually we managed to arrange the cooler, some drier ventilation tubing and the cannon box so that the dry ice vapors poured into the box. Again my daughter was learning about science. We didn't exactly know where we were going at the outset, but we had a general idea of the theory.

After filling the box with the vapors we borrowed a spatula from the kitchen, and gave the plastic bag a big whack! Out popped a burst of C02 vapor that shot across the room! My daughter thought this was great. Why does it do that? Can we do it again? She was hooked!

Next came a balloon. We chipped off a few more pieces of dry ice, and I placed them in the balloon. We put the balloon to one side.

Next was the soda pop bottle. We placed a few ice chips inside the bottle together with some water. We placed a balloon over the top, and the balloon instantly inflated! Again, she was hooked! By this time the original balloon had started to inflate by itself. Why does it do that? How was it that we put a solid object in the balloon and yet when you open it up, there is only gas inside?

We had a great day. My daughter too young to "get" all the science that was going on, but she does remember the day clearly. And she sees how you can experiment until you get something right.

One day perhaps when she is in high school she'll look back and remember her crazy Dad playing around with the ice that wasn't wet. I think I have planted a seed.

Here are some questions I asked my daughter throughout the day:

• Why do they call it dry ice? When it "melts" where does it go?
• If we store the dry ice in the refrigerator will it stay frozen? [Do the experiment and ask her where it went the next morning!]
• What is the "fog" you see when dry ice bubbles in warm water?
• What do you think we could use dry ice for? [Hint: we can go back over to the ice cream store if you get all these questions correct!]

Important Safety Note: We had fun, but we were very careful to ensure that we had the appropriate safety equipment including safety glasses and insulating gloves as well as adequate ventilation. Please remember that dry ice can be dangerous, and that it may pose a suffocation risk in enclosed areas. An adult should always supervise activities such as this. Also, please be aware that handling dry ice can be harmful and that placing it into a closed container can lead to serious explosions.