A major scale is a group of eight notes that gives the familiar sound:
You now know enough notes to play the C major scale. To play the C major scale smoothly you will need to play the F note with your thumb. Do this by moving your thumb underneath your second and third fingers on the way up the scale. On the way down the scale, move your second and third fingers over your thumb. This is called the crossover. The small numbers placed above, below or beside notes on the staves tell you which finger to play each note with. Be sure to use the correct finger.