In this article we present a project that includes physical measuring, examination and modelling task. The main objective of this article is to present the theory of thermoacoustic oscillations; for this purpose, a simple Rijke-type thermal device was built. The Rijke tube is essentially a pipe open at both ends with a mean flow and a concentrated heat source. It serves as a convenient prototypical example to understand the thermoacoustic effect since it is a simplified thermoacoustic resonator; once excited, it is capable of creating a sustained sound when thermal energy is added, under certain conditions. This article discusses Rayleigh's instability criterion and a simplified mathematical model of the thermoacoustic phenomenon in the Rijke pipe. The article gives a qualitative understanding of the conditions under which thermoacoustic instability occurs. We employed the electrically heated Rijke tube in our thermoacoustic school project work; the aim of our project is to help students increase their knowledge about thermoacoustics. (Contains 4 figures.)