So, My question is, How do you tell what Key a piece is in. I bought a Disney Piano book with the music for all these disney songs this weekend, but I don't know how to tell the key.

I guess it was just something I missed in class, and never asked because he (my music teacher) always told us before he taught the song.

Can someone help me please! Thanks a lot!

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The key signature is right at the start of the piece just before the time signature and just after the clef.

The number of sharps/flats will tell you the key.

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You can probably look up 'key signatures' online and learn what key is which.  It's not too hard to learn once you notice the pattern.

I don't know how much you know about scales, so I'll act as if it's nothing: there's a pattern of tones and semitones that makes up major/minor scales. When you use this pattern from different notes, you end up with different flats and sharps, which is why each scale is in a different key. However, for every major scale, there is a minor in the same key: C major and A minor, F major and D minor...so the key signature only narrows it down to 2 scales, unless it's a weird piece that's been put in one key in the key signature but is actually written in another (or if you're looking at a section that modulates to a different key, then there will often be no marked key change).

The way to tell is to look at the accidentals. For example, a piece written in C major will probably stick mostly to the notes of C major, but a piece in A minor will be full of accidental G sharps, even though the key signature is the same. You can also look at the first and last notes of the piece: a piece in A minor is likely to start and end on A (or sometimes the dominant, the 5th note of the scale), whereas a piece in C major is likely to start and end on C.

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