Every student gets an Otter Pop in this activity that walks the kids though the scientific process. High engagement from the moment that the Otter Pop's are revealed in class.
Each student will make a hypothesis as to how to keep the Otter Pop frozen the longest (that does not include putting it in the freezer or refrigerator!) Then students will carry out an investigation to find out whether their data supports their hypothesis or not. The best part is that everyone can eat their homework at the end of this activity.
I purchase a bulk box of Otter Pop's (or similar) from my local warehouse distributor. Very cheap lab and a lot of fun.
Use this at the start of the year or incorporate it into a unit on insulators and conductors.