The study points to the contrast between the scepticism that in teaching circles in the 1920s and 1930s led to pedagogical positions relating to learning science by discovery – close to the heurism – and the enthusiasm that existed in Spain, in the institutional contexts known as renovators, towards these positions. One of the centres in which these active methods were applied was the Instituto-Escuela de Madrid (Retiro Section), whose results are set out in the works made up of Andrés León Maroto and Miguel Catalán, located between the manual and the report of the classroom experiences, published in 1931, 1934 and 1935. By examining the practical exercises in question, and taking into account the studies on the replicability of historical experiments and the transfer of know-how, we will verify the concrete effects of the proposed revisions of the methods active in the centre, considered to be one of the benchmarks of the pedagogical reforms.