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Curricula / CTC Math

CTC Math, with a teacher who answers.

Why parents choose CTC Math

  • Short video lessons kids follow alone
  • Graded right away
  • Every grade level in one plan
  • Kids move at their own pace
Try a lesson freeNo card needed
Your course · Grade 8
Unit 8 · Volume
Unit 9 · Square roots
Unit 9 · Pythagorean theorem
Unit 9 · Distance
Unit 10 · Functions
HeySensei
Unit 9 · Pythagorean theorem
a² + b² = c²9 + 16 = 25c = 5
SReady when you are. Let’s pick up right here.

How we teach CTC Math

Same topics, same order. Here’s Grade 8, Unit 9: the Pythagorean theorem.

Grade 8 · Unit 9 · The Pythagorean theoremTrial lesson
  1. a² + b² = c²
  2. 3² + 4² = 9 + 16the two small squares
  3. c² = 25, c = 5the big square

SenseiDraw a square on every side of a right triangle. Something surprising happens.

Study notes for every lesson

Each lesson comes with one page of notes in the order of the course: the new idea, a worked example, and the mistakes to watch for. Your kid can look back at them any time.

Grade 8Unit 9 · Pythagorean theorem

The new idea

In a right triangle, the squares on the two short sides add up to the square on the longest side.

Worked example

  1. a² + b² = c²
  2. 3² + 4² = c²
  3. 9 + 16 = 25
  4. c = √25 = 5

Watch out for

  • Using it on a triangle with no right angle
  • Making c a short side
  • Forgetting the square root
HeySensei · one page per lesson

Where CTC Math gets hard, and what we changed

What parents struggle with most, and what we did about it.

What parents struggle withWith HeySensei
The whyShort videos show how to do it, rarely why it works.Sensei explains the why at the whiteboard and answers when your kid asks.
Clicking throughAnswer-only questions are easy to click through or guess.They work on paper, and every line is checked from a photo.
Getting stuckWhen the video doesn’t help, there’s nobody to ask.A hint on the exact step they’re stuck on. Never the answer.
The practiceThe same questions for every kid.Practice rebuilt every day from what your kid missed. Harder and faster once it’s solid.
Your recordsA percentage per topic.You see which skills are solid, which slipped, and a predicted grade for the year.

“He used to click until something turned green. Now he has to show his work, and he actually gets it.”

Mom of 2 · son in 7th grade · came from CTC Math Grade 7

Every CTC Math level, grade 6 to 12

LevelUsual gradeTopics
Grade 66all
Grade 77all
Grade 88all
Algebra 19all
Geometry10all
Algebra 211all
Pre-Calculus / Calculus12all

Every topic is mapped. Tell us where your kid is and we pick up there.

CTC Math questions

Do we have to cancel CTC Math?

That’s up to you. Tell us the level and the topic and your kid picks up there.

My kid is used to the computer. Is paper a big change?

The lesson is still on screen. Only the practice moves to paper, and a photo sends it in.

Are there tests?

Yes. Topic tests in the same places, graded for you, with what they mean.

My kid is ahead of (or behind) the course. What happens?

Start where they are. If they already know it, they move ahead. If something from earlier is missing, we go back and fill it in first.