Music Theory
Khan Academy
Music Basics
Lesson 1: Note values, duration, and time signatures
Lesson 2: Rhythm, dotted notes, ties, and rests
Lesson 3: Meters in double and triple time, upbeats
Lesson 4: Meters in 6, 9, and 12
Lesson 5: Review of time signatures – Simple, compound, and complex
Lesson 6: Constant versus changing time, adding triplets, and duplets
Reading Music
Lesson 1: Staff, names of notes, treble clef
Lesson 2: Ledger lines and the octave
Lesson 3: Bass clef, grand staff and the octave
Lesson 4: Reading music in treble clef and the C Major scale
Lesson 5: C Major scale in bass clef and reading in bass clef
Lesson 6: Alto and tenor clefs
Lesson 8: Natural sign, more on accidentals and key signature
MusicTheory.Net
The Basics
Lesson 1: The Staff, Clef, and Ledger Lines
Lesson 3: Measures and Time Signature
Lesson 6: Steps and Accidentals
Rhythm and Meter
Lesson 7: Simple and Compound Meter
Scales and Key Signatures
Intervals
Chords
Lesson 17: Introduction to Chords
Lesson 20: More Seventh Chords
Lesson 21: Seventh Chord Inversion
Diatonic Chords
Lesson 23: Roman Numeral Analysis: Triads