We present a sequence of two physics experiments, designed for use with secondary students, which investigate the specific heat of sand, both qualitatively and quantitatively, without a calorimeter. We use two LM35 temperature sensors and an Arduino prototype board for data acquisition. The results are good and allow teachers to discuss the behaviours of water and sand in the heating and cooling processes. Our proposals are suitable for use in the teaching of high school students and lead to meaningful learning about this physical property.