In accordance with the invention, thin bodies of plastic, such as sheets or strands, with substantially different thermal coefficients of expansion, are laminated together to make plastic bodies that move in response to temperature change. The thermally movable plastic can be secured to a suitable base to make a variety of devices. In one embodiment, the thermally moveable plastic can be used in a beverage safety lid. The safety lid is particularly useful as a lid for hot drinks, such as hot coffee, soups and other foods.