Improving the connection between the microscopic and macroscopic approaches to thermodynamics in high school

In this article we discuss a teaching learning sequence on basic thermodynamics, spanning the first and second principle, and the concepts of irreversibility and entropy, intended for use in secondary school. With respect to previous works we emphasise the importance of discussing the compatibility between the time reversal symmetry of Newton’s laws and the irreversibility embodied in the second principle of thermodynamics in order to completely exploit the possibility of connecting the microscopic and macroscopic perspectives. The sequence was tested in an Italian secondary school, and the results obtained from a questionnaire which combines several test items used in previous studies at university level are consistently comparable with or better than those reported for undergraduate students on the same questions over a range of topics. Thus, our work suggests that the microscopic approach is a viable option for the teaching of thermodynamics at the secondary school level; and the understanding of macroscopic concepts is not impaired, but possibly enhanced, by the adoption of such a teaching strategy.