bythreedu · Math Tracks · Curriculum v1.0 · 2026

Proof, measurement,
and the logic
of space.

A complete Geometry course from undefined terms and angle pairs through transformations and volume. Built around understanding why — every theorem is derived, every formula has geometric meaning, and every proof is structured reasoning.

Total Lessons24at your pace
Units8progressive phases
Assignments8+problem sets
DestinationTrigonometry
Ready
00Approach
Course Philosophy

Reasoning Before Formulas

Geometry is the first math course that explicitly requires proof. This course treats that seriously — every theorem is derived from simpler results, and every formula is explained geometrically. Students who understand why the Pythagorean theorem works cannot forget it.

Diagrams First, Equations Second

Every geometry problem in this course is set up with a labeled diagram before any equation is written. The diagram is not decoration — it is how you know which relationships apply. Students who diagram first make far fewer errors and catch them when they do.

01Curriculum
Learning Path
01
Unit 1 · Weeks 1–2
Foundations: Points, Lines, and Angles
3 lessons · Basic definitions · Angle relationships · Geometric notation
undefined termsangle pairsgeometric notation
+
02
Unit 2 · Weeks 3–5
Triangles: Congruence and Properties
3 lessons · Triangle classification · Congruence shortcuts · Triangle inequalities
congruence shortcutstriangle sumtriangle inequality
+
03
Unit 3 · Weeks 6–8
Similarity and Proportional Reasoning
3 lessons · Similar figures · AA, SAS, SSS similarity · Proportional sides
similarity shortcutsscale factorproportional sides
+
04
Unit 4 · Weeks 9–11
The Pythagorean Theorem and Right Triangles
3 lessons · Pythagorean theorem · Special right triangles · Applications
Pythagorean theorem30-60-9045-45-90
+
05
Unit 5 · Weeks 12–14
Quadrilaterals and Polygons
3 lessons · Quadrilateral properties · Polygon angle sums · Coordinate geometry
parallelogram propertiespolygon angle sumcoordinate proof
+
06
Unit 6 · Weeks 15–18
Circles
3 lessons · Circle parts · Arc and angle relationships · Equations of circles
central anglesinscribed anglescircle equation
+
07
Unit 7 · Weeks 19–21
Area, Surface Area, and Volume
3 lessons · 2D area · 3D surface area · Volume of solids
area formulas derivedsurface areavolume
+
08
Unit 8 · Weeks 22–24
Transformations and Capstone
3 lessons · Rigid motions · Dilations · Capstone review
translationsreflectionsdilations
+
02Capstone
Final Exam Simulation

The capstone is a comprehensive problem set across all 8 units. Every missed problem gets a written correction — not just the right answer, but the reasoning that should have been applied.

○
Gap Review
Two weakest units revisited before the exam simulation.
○
Timed Final Exam
Full-length, independent, same conditions as a real exam.
○
Written Corrections
Every missed problem corrected with reasoning — not just the right answer.
○
Trigonometry Readiness Review
A final session on what Trigonometry will demand from day one.
03Investment
Pricing Options
Location
per Session
$125
1.5 hrs · online only
Session length
  • —Flexible scheduling
  • —1-on-1 focused attention
  • —No long-term commitment

Best for trying the curriculum before committing to a plan.

Popular
per Month
$500
4 sessions · 1.5 hrs/session
Frequency
Session length
  • —Session notes after every lesson
  • —Async DM support between sessions
  • —Priority scheduling

Adjust frequency and session length above — price updates automatically.

Per Semester
$2,000
16 sessions · 1.5 hrs/session
Term length
Frequency
Session length
  • —All 8 units — full course arc
  • —Session notes after every lesson
  • —Capstone exam simulation + written corrections
  • —Trigonometry readiness review at completion

The full Geometry arc in one commitment.

📍
In-person available · NYC onlyMonthly and semester plans can be done in-person. Select “In-person · NYC” above to see adjusted pricing.
04Contact
Let's Talk

Working through geometry and hitting a wall on proofs? One session is enough to find where the breakdown is.

What do I need to know coming in?+
Are lessons online or in-person?+
Can I switch plans later?+
What if I need to reschedule?+