Piano tablecloth tool

Which is a better material used to make a homemade thermos; aluminium, plastic or paper? - homemade aluminium boat

I'm doing this science experiment. Conditions did little to indicate the different sections (each) from a different material and pour some hot water in them. I have to see how long it would take would be to cool the water in each cup. so do u think the material will keep the water hot for more?
Aluminum, plastic or paper? I like to have .. from the best materials.
Thanks