Abstract: A method and device for teaching the comparative measurement of heat flow through and into selected sample materials. The device includes a container constructed of relatively low heat conductive material and adapted to be partitioned into at least two identical chambers. Means for holding sample materials, filling the identical chambers with insulation, covering the container, heating one chamber of the container, measuring the temperature in the identical chambers, and other means for adapting the device for selected investigations are removably received within the container, making the teaching device flexibly adaptable to a variety of teaching uses. The method for teaching the comparative measurement of heat flow through and into selected materials includes exposing at least one heat receiver to a selected source of radiant energy under selected conditions.