Ice Cream in a Bag

So last Friday I was able to go to the Chemistry class of 4th eso (students are equivalent to being Sophomore's in High school).
I had been asked to come to the Chemistry class, so after racking my brain from my high school/middle school Chemistry classes, I finally decided that making ice cream in a bag was one of my favorites. It shows chemical changes with salt and it lowers the temperature of the ice when the Na is splitting from the Cl. I remember having to take the temperature of the ice in this process, and the detailed lab write up we had to do for this. Including the Scientific Method - which I hated then but now it makes sense that we had to do that...
The students in this class though - didn't have to do any of that. I basically told them step-by step what they needed to do AND I gave a description of what was happening with the chemical changes and WHY we were doing this experiment. 
We had most of the supplies we needed (finding Vanilla extract here is impossible - so we just had them make chocolate flavor instead) The professor bought the wrong kind of pint-sized bags - I was a little disappointed about that because the zip-lock works SO MUCH BETTER. He bought the ones you tie - which makes the experiment a LITTLE more challenging. Even without, the experiment worked just like I wanted, and the students really liked it.
They were too funny because the ice gets SUPER cold. I warned them of that, and told them to try and put their sleeves over their hands to do it. Some of them whined that the bag was too cold, I had to explain that they needed it be that cold for the liquid in the other bag to turn more solid - just like ice cream. haha. After about 7 minutes of rocking the bag of ice back and forth, I checked all of the students, and most of them did a great job and their liquid was cold and solid like ice cream.
It was really neat to be able to go to a class other than English and do an experiment. Another chemistry professor came in to watch the experiment and decided to do the lab with her class as well - it was a good feeling.
Glad it all worked out, maybe we can do it next year too!

Until Next time

Tori