Several techniques were developed to obtain experimentally the specific heat of solids and liquids and efforts has been done in order to build low cost experiments to use at high school level. In this work we propose a simple way to obtain specific heat of solids and liquids. Through calibration cooling curves we are able to estimate graphically the heat power loss of the system and also obtain the specific heat of the aluminum. This approach allows introduce a discussion on the actual dynamic process that is heat change between two bodies.