As a German I can assure you that false friends are something you scare away all pupils (regardless of age). I have very intense memories of our English teacher correcting us again and again.
Regarding the composita in German: we are moving more towards the English approach by splitting these word monstrousities with hyphens. E.g. Donaudampfschifffahrtsamt may be spelled Donau-Dampfschifffahrts-Amt. Its way easier to read and write. While the hyphenated spelling is not something that is used often officially, it got more popular in the last decades.
Ah, the old reddit hand-o-roo