FWIW I just got max level (it's a non-Latin language so the initial exercises are all repetitions of recognizing certain glyphs and their combinations) and it t

FWIW I just got max level (it's a non-Latin language so the initial exercises are all repetitions of recognizing certain glyphs and their combinations) and it turns out that there's nothing special about it except you get to repeat it instead of moving on to a higher difficulty. So "it's actually not possible to beat it" is probably more of a calibration issue than a blatant money grab. The only reward is more XP.