It's well established that people learn best when they teach, and that's why there's a "Teach Back" method. We use that often in healthcare, asking patients to "teach" us back what we've explained to them, in their terms, just to make sure that they understood what we've said.
I was getting my piano kid today to play arpeggios, and this arpeggio pattern suddenly hit me. It's difficult to make them remember arpeggios, especially when there are 24 variations (5 black key major, 5 black key minor, 7 white key major, 7 white key minor) x 3 (because there's right, left and hands together). The difficult ones are the black keys, because its rarely played at their stage.
So while I was wrecking my brain on how to make her remember this whole lot of mess, it occured to me that there is this recurring pattern. Black - white - black. Most of the keys are played in this black-white-black pattern, except for a few special ones.
Let me explain. Arpeggios are made up of the 1st, 3rd and 5th notes of the key they are playing. For example, C major would be C (1st), E (3rd) and G (5th). So they are ONLY suppose to hit this 3 notes for arpeggios. Straight forward? Yes. But not until you have 24 variations of it.
So for black keys, lets start with C# minor. C# will be C# (1st), E (3rd) and G# (5th) according to the key signatures for C#. (Note: those with a # will be black key). So, the first note is black, second is white and third is black.
Lets move on to F# minor. F#, A, C#. Again, black white black.
G# minor. G#, B, D#. Black white black.
Fingering for the above formation is simple. 2 1 2 4 for right, 2 1 4 2 for left. Just start with the 2nd finger, it will not go wrong.
Also note that # pairs with #. meaning if its F#, it will go with C#, not Cb.
I left out D# minor and Bb minor because they are the special ones.
How about major?
Db major - Db, F, Ab (black white black)
Eb major - Eb, G, Bb
Ab major - Ab, C, Eb
Again, black white black. Fingering is the same as minor. And b will pair with b.
F# major and Bb major is special, so i left it out.
And this already solved 60% of the black key arpeggios. The special ones are even simpler, with D# minor and F# major having all black keys and Bb major and minor being the odd one out (I shall not elaborate at this point).
In summary,
1. remember the 1st, 3rd and 5th note for the key (e.g. C# minor, remember C, E and G)
2. add in the black keys (so for C# minor will be C# and G# because its a black white black pattern)
3. play with the fingering 2 1 2 4 or 2 1 4 2 (right and left hand respectively)
4. score!!!!
BUT.
My piano teacher did not teach me this. I had to dead memorise (死背) all my scales. It was tragic. I don't blame her though. She did do a good job trying to teach me (I was a horrendous student) and helping me pass my exams.
Anyway, through teaching my kiddos, I also learnt how to better play my scales (not only arpeggios, I also stumbled on a pattern for playing minor scales). I figured out so many tricks and patterns while I was repeatedly going through scales with them. It was rewarding :) I hope they find this helpful during exams as well.
Teaching is two-way for me. I give, I gain. I gain, I give :)