The G major scale and key signature: one sharp, F sharp

After this lesson you can read a key signature of one sharp and play the G major scale and Ode to Joy in G.

Once you can play the C major scale, a surprising thing becomes possible: you can play a major scale starting on almost any note, as long as you keep the same pattern of whole and half steps. The first new key most pianists meet is G major. It needs just one black key, F sharp, and it introduces an idea that will save you a great deal of reading effort: the key signature.

Building a major scale on G

The C major scale follows the pattern whole, whole, half, whole, whole, whole, half. Try copying that pattern, starting on G and using only white keys:

G to A: whole step. Good.
A to B: whole step. Good.
B to C: half step. Good.
C to D, D to E: whole steps. Good.
E to F: only a half step. The pattern needs a whole step here.
F to G: a whole step. The pattern needs a half step to finish.

The last two steps are the wrong way round. The fix is to raise F by a half step to F sharp. Now E to F sharp is a whole step, and F sharp to G is a half step, just as the pattern wants. So the G major scale is G A B C D E F♯ G.

The G major scale: the same step pattern as C major, with F sharp as its only black key

That F sharp is not decoration. It is the seventh note of the scale, and its half step up to G gives the scale its strong sense of arriving home. Play the scale once with F natural by mistake and you will hear it sound oddly unfinished.

What a key signature is

A piece in G major might have dozens of Fs. Writing a sharp in front of every single one would clutter the page. Instead, the composer writes the sharp once, at the start of every line, straight after the clef. This is the key signature.

In the treble clef the sharp sits on the top line, which is F. In the bass clef it sits on the fourth line up, which is also F. Either way, it means the same thing: every F in the music is played as F sharp, in every octave, all the way through, even when there is no sharp printed beside the note.

The G major scale with its key signature: one sharp on the F line, so no sharp is needed beside the F

Notice that the F near the top of that scale has no sharp beside it. The key signature has already told you. This is the single most important reading habit for this lesson: read the key signature before you play a note. One sharp means G major, and it means F sharp everywhere.

The G major scale, right hand

The fingering follows the same plan as C major. Put your right thumb on the G above middle C.

Play G, A, B with fingers 1, 2, 3.
Pass the thumb under to C.
Play D, E, F sharp, G with fingers 2, 3, 4, 5.
Coming down, play G, F sharp, E, D, C with 5, 4, 3, 2, 1, then cross finger 3 over onto B and finish 3, 2, 1 on B, A, G.

Finger 4 lands on F sharp. Let the hand move slightly forward into the keys so the fourth finger can reach the black key without the wrist bending sideways.

Right-hand fingering for G major: 1 2 3, thumb under to C, then 1 2 3 4 5 with finger 4 on F sharp

The left hand

Start with finger 5 on the G well below middle C, at the bottom of the bass staff. Play G, A, B, C, D with 5, 4, 3, 2, 1, cross finger 3 over onto E, then 2 on F sharp and 1 on the top G. Coming down, the thumb tucks under after E: 1, 2, 3 on G, F sharp, E, then 1, 2, 3, 4, 5 on D, C, B, A, G.

In tunes, the left hand often meets F sharp inside a chord. In the Academy's arrangement of Ode to Joy in G, the left hand alternates between two chords, and the second contains F sharp. The key signature applies there too.

Left-hand chords from Ode to Joy in G: the middle note of the D chord is F sharp, given by the key signature

How to practise it

Name the key first. Before each practice, point to the key signature and say aloud "one sharp, F sharp".
Find every F sharp. Before playing anything, scan the music and touch the F sharp key for each F you see.
Right hand scale, slowly. Up and down with the fingering above, one note per beat, finishing on a half note.
Left hand scale, slowly. The same, separately.
A tune in G. Play Ode to Joy in the key of G. The melody itself has no F, but the left-hand chords do, so this is a good test of whether you read the key signature for both staves. Later, try the version on the Ode to Joy song page and check its key signature before you start.

Common mistakes

Applying the sharp to only one octave. The sharp on the top line covers every F, high or low, not just the F on that line.
Forgetting the left hand. The bass staff has its own key signature on the fourth line. It is easy to read it in the treble and miss it in the bass.
Thumb under too early. In G major the thumb passes under after B (finger 3), not after A.
Flattening the hand to reach F sharp. Move the whole hand a little towards the fallboard instead.

Try it in Pianuvo

In the Academy lesson you play the G major scale with each hand and then Ode to Joy in G, and each exercise listens as you play, through the on-screen keys, a MIDI keyboard or a real piano heard by your microphone. Find it in Unit 5: Sharps, scales and G major.