You could use thermodynamics and a simple styrofoam cup calorimeter and calculate it. It would have to be an object made of something you knew the specific heat for, though. An infrared thermometer is probably easier. :)
That is good to know! The whole practicum had a different goal then exact measuring, but it made us wondering how one could measure it. I will share it with dd. This our first chapter of Physical Science, Thermodynamica is one of the latter chapters.