Thomas and Julie wanted to find out which material would insulate their teacher's coffee cup and keep
the coffee hot for the longest period of time. They first wrapped her cup
with bubble wrap and recorded
the temperature of the coffee once every 15 minutes for 2 hours. They repeated the investigation, this
lime using newspaper instead of bubble wrap, but they got the same results for both materials. What
could they do to make sure their results are valid?!?!
