If a child starts to play the piano at six (at or about the beginning of Grade 1) with a teacher, reading sheet music from the first lesson, at what point can one reasonably expect the pupil/teacher to move on to G or F? When is it reasonable to expect D and B♭ to be played (and read)? At what point can a parent expect that the teacher will introduce reading the relative minor keys?
I have the impression that this depends on the style of piano teacher one hires. A teacher adopting a classical repertoire will introduce a variety of keys sooner, whereas a teacher using a folklore or popular repertoire will remain for years in C-major. Can you clarify?
This is a simple statistics question. Music teachers will typically not design courses from scratch. They will normally pick a first book in a series, and the series will dictate what is introduced when.
Each book series comes in a sequence: Book 1, Book 2, ... to Book 10, say.
A motivated student might finish each "book" in considerably less than a year. A less motivated student might take a bit more than a year.
Is there an established pattern for when key signatures are introduced? Is there a "typically we see ..." rate for introducing new keys?