The session: between 15 and 25 minutes, in five steps
A lesson is not “putting a song on”. It is five chained steps — listen, vocabulary, play, sing and the Challenge — on the same song. That chaining is what turns 15 minutes of screen into 15 minutes of practice.
The repetition: 5.9 re-encounters per word
Every new word comes back, on average, in 5.9 LATER lessons — not inside the same song, which would be repeating for the sake of it. Each lesson introduces 3.2 new words and recycles 18.9. It is deliberately few: learning a few and meeting them again is what fixes them.
The level: a scale with declared CEFR equivalence
Every lesson declares its level and its CEFR equivalence. The scale has 5 levels and covers Pre-A1 to A2: the range where primary school lives. It doesn't stretch further because at this age it doesn't need to.
What you are told: progress, not surveillance
You see which words they master, which lessons they completed and how long they practised. You do not see — and neither do we — any recording of their voice: it is processed to give feedback and discarded on the spot. No ads and no third-party trackers.