Regardless of which instrument you play, and whichever style of music you like, Music Theory will help you to understand what makes music work and how to write your own. Topics covered in the theory program include key signatures, scale spellings, harmony, harmonic analysis, clefs and music reading, time signatures, chord progressions, transposition and many others.
Music Theory is closely tied to Ear Training. GCNW uses the series Sound Advice (Frederick Harris Music) for all students to cover Ear Training and Theory. Many examinations have a theory co-requisite in order to get a performance score (for example the Royal Conservatory Music Development Program). Other examinations (LCM & RGT for example) include theory and ear tests as part of the assessment. Sound Advice has proven to be a clearly written and exhaustive training series. All students should begin level 1 within 1-2 years of starting lessons.
Having a firm and confident proficiency in Theory and Ear Training helps you learn music faster, interpret it better and memorize it easier. You'll get much more productivity out of your regular lessons the better you are at these musicianship skills. In the past, public schools used to offer some musicianship oriented classes, but this is no longer the case, so it's important to get on top of this oft-neglected topic as soon as possible.
Students who complete all 8 levels of Sound Advice can subsequently begin Basic Harmony (Sarnecki), which is required for students taking the Harmony 1 examination.
History 1 is also a requirement for RCM level 9, and can be started at any point (usually around Sound Advice level 7).
Composition and Counterpoint are also topics that can be included based on individual needs.