C's on the Staff
On the Grand Staff the Cs are reflected. This creates a set of C landmarks across the four octaves shown here.
The two Middle C's shown in the diagram below are the same note.
The Cs, one octave higher and one octave lower than middle C, land on the 3rd space of the staff, reflecting a span of eight notes higher or lower than middle C.
The Cs, two octaves higher and lower than middle C, are line notes for which the staff must be extended by two ledger lines. They are easily recognizable and make good landmarks for reading notes above and below the staff.
c
c
c
c
c
c
same note
C
C
To denote the C's three octaves distance from middle C, a sign 8va is placed above or below the note to direct the musician to play the note another 8 notes higher or lower than it is written.
Read Music Method makes teaching beginners delightfully fun from day one. Students have "Ah, ha" moments every lesson.
How to Read Music
An interesting item: To indicate a jump of two octaves, a sign, 15va, could be placed above or below a note. Fifteen is the number of white keys involved in the interval of two octaves.