Music lessons teaching a polular song for each key

For example piano lessons using the notation on Bach Bass rules (figured bass).


For the C major scale or key Imagine - John Lennon may be a good example.


The code for each 4 bar measure:


C imagine there's no
F heaven
C9 resolved to C it's easif you
F try
C9 resolved to C
...
F imagine
E246 all the
D7 people
D246 ...
G ...
G7 ...


Or it could be Let it Be - Beatles, again which is also C major key. Or Whiter Shade of Pale - Procol Harum (based on Bach air on G string).



Next song could be one in A minor, the relative of C major. Both have only white keys.


Next song could be one in G major and then one in its relative E minor. They both have all white keys except F which is F sharp. So they define the same 7 chords.


Then D major and B minor etc.


Reference:


Bach bass rules:
https://normanschmidt.net/scores/bachjs-general_bass_rules.pdf