By Heather Rathnau. Edited by Heather Rathnau. For General Music Theory. This edition: all instruments. Music theory for a student that has completed the Grade Three workbook; Also a great level to start an older beginner in 7th or 8th grade. Focuses on the keys of C, G, D, A, E and F Major and introduces the 8th note. Level: Early Intermediate level. Workbook. 60 pages pages. Published by Theory Time Partners.