It's a school thing and I can make an ice cube frozen for 3 hours and you can only use household materials which means NO buying other stuff from stores and other places. THe container also has to be less than 14x14 Inches. My container is a normal box with tin foil wrapped around it and some styrofoam in the box. It's ok...... ANY TIPS THO???????????(P.S. TY for the help)