Students sort cards into three categories that describe heat transfer; conduction, convection and radiation. Can be printed on regular copy paper. For durability for use each year or as a center activity it may be helpful to print on construction paper or tag board.
I use this as a baseline activity. Students work in pairs or groups to sort the cards before learning takes place. After instruction, students are invited to resort cards. I also sometimes run class sets and after learning students glue the categories and examples into their journals as a reference tool.