🎯 Where This Came From
Four students taught unit circle lessons: Ana Fernandez, Aaron Hagaman, Katelyn Smith, Emma Stenger
Problems identified across their lessons:
- Sign errors by quadrant — Ana's students got numerical values right but applied wrong signs (Q1-Q4 confusion)
- Decimal bypass — Aaron's students memorized decimals instead of understanding triangle relationships and exact values
- Coterminal angle confusion — Aaron's students couldn't "enter the circle" from angles like 405° or -135°
- Students could work within the circle but struggled connecting it to real angle measures
Design goal: Build three targeted features, each addressing a specific misconception from field data.
🛠️ Design Decisions
Feature 1: Predict Signs Mode (purple button)
- From Ana's feedback: "Requiring students to PREDICT the sign BEFORE they calculate"
- Students choose +/− for sin/cos/tan, then check answers
- Coordinates hidden as "( ?, ? )" until prediction checked
- Correct predictions turn green, wrong turn red
Feature 2: Exact Values for Special Angles
- From Aaron's feedback: "Fractions and triangle relationships are the conceptual core"
- Shows √2/2, √3/2, ½ in bold white when at 30°/45°/60°/90°
- Decimals shown below in muted gray (de-emphasized)
- Prevents students from bypassing the conceptual understanding
Feature 3: All Quadrants Simultaneously
- From Aaron's feedback: Students couldn't connect coterminal angles across quadrants
- Shows reference triangles in all four quadrants at once
- Color-coded by quadrant (Q1 amber, Q2 blue, Q3 violet, Q4 green)
- Terminal quadrant gets larger dot to show "where you landed"