Forester's house extant in Schwetzingen © Prof. Dr. H. E. LessingKarl Drais has finished his studies, because his examination for forestry squire was set, but then this was cancelled for an indefinite period. What should he do now? Drais joins his uncle at the forester's house of Schwetzingen and works as an assistant teacher in his uncle's forestry school. He teaches to the future foresters mathematics and drawing maps, physics and chemistry, as well as German language and logics. He also relieves his uncle from correcting the essays of the pupils.

For his uncle had hopes to become professor at the university of Heidelberg. The relevant minister von Reitzenstein wrecks these plans, whereupon the disappointed uncle applies for a transfer to Freiburg leaving Karl behind.
In 1807 finally Karl Drais can have his examination that he passes.