The course goes minor. The three forms of minor scales, how keys relate to one another, other scales like chromatic and pentatonic, intervals by size and quality, transposing instruments, and the timbre, melody, and texture that give music its character.
Thirteen topics from the College Board CED, in order.
Topic 2.1
Minor Scales
The three forms — natural, harmonic, and melodic minor — and how they differ.
Topic 2.2
Relative Keys
Finding the relative minor of a major key (and vice versa) and notating its key signature.
Topic 2.3
Key Relationships
Parallel, closely related, and distantly related keys.
Topic 2.4
Other Scales
Chromatic, whole-tone, and pentatonic scales.
Topic 2.5
Interval Size & Quality
Naming intervals by letter-count (size) and half-step content (major, minor, perfect, augmented, diminished).
Topic 2.6
Interval Inversion & Compound Intervals
Inverting intervals (sizes sum to 9) and intervals larger than an octave.
Topic 2.7
Transposing Instruments
Written vs. sounding (concert) pitch for instruments like the B♭ clarinet and trumpet.
Topic 2.8
Timbre
Tone color — what makes instruments and voices sound distinct on the same pitch.
Topic 2.9
Melodic Features
Contour, range, and conjunct (stepwise) vs. disjunct (leaping) motion.
Topic 2.10
Melodic Transposition
Moving a melody to a new pitch level while keeping its intervals intact.
Topic 2.11
Texture & Texture Types
Monophony, homophony, and polyphony, and how to hear them.
Topic 2.12
Texture Devices
Imitation, doubling, and other ways composers thicken or vary texture.
Topic 2.13
Rhythmic Devices
Augmentation, diminution, hemiola, and other rhythmic transformations.
About Unit 2
Unit 2 extends the fundamentals into minor keys and richer musical detail. You'll build the three forms of minor scales (natural, harmonic, melodic), map how keys relate to one another (relative, parallel, and closely related), meet other scales like chromatic and pentatonic, and learn to name any interval by its size and quality.
The unit then turns to how music actually sounds: transposing instruments (written vs. concert pitch), timbre, melodic features like contour and motion, and the three basic textures — monophony, homophony, and polyphony.
Unlike most AP courses, the College Board does not assign a percentage of the exam to each unit — the exam is weighted by section (45% multiple choice, 45% free response, 10% sight-singing). But Unit 2's minor scales and intervals are essential groundwork for the harmony and voice-leading units that follow.
Unit 2 develops three of the four AP Music Theory Big Ideas:
Big Idea 1
Pitch — minor scales, key relationships, and intervals
Big Idea 2
Rhythm — rhythmic devices like augmentation and hemiola