Maths · KS3 Y8 · Number

Index notation

Index notationFree7:01Heddy Score 3 of 7, below the standard

What you need to know

  • In 5², the 5 is the base and the 2 is the power (index), which says how many 5s to multiply together.
  • 5² means 5 × 5 = 25, not 5 × 2 = 10.
  • A power of 2 is read 'squared' and a power of 3 is read 'cubed'.
  • Repeated multiplication such as 3 × 3 × 3 × 3 × 3 × 3 can be written as 3⁶, which equals 729.

In this clip

Runs 7:01, from 0:04 to 7:05 of the full video.

Heddy Score3/7, Below the standard
See the seven stars
  • Trusted source · passed. The creator's own upload, live and playable here.
  • On the map · not judged yet. A teacher watched it: it mainly teaches this map topic.
  • Spec-true · not judged yet. Accurate, and right for the current UK specification.
  • Focused · passed. One idea, short enough to watch in one go.
  • Accessible · passed. Good captions, clear sound and pictures.
  • Safe for children · not judged yet. Right for 11 to 16 year olds, with no sales pitch.
  • Proven · not judged yet. Earned from our students: they learn from it, find it helpful and watch it to the end.
★ passed · ☆ pending · ✕ failed
Our students

Not enough students yet

Our own students' answers. These are what move ★7 Proven.
On YouTube

990K views · 9.83K likes · Math with Mr. J 2.03M subscribers

As reported by YouTube on 2026-11-02. Not part of the Heddy Score.
How the Heddy Score works

Why we picked it

A clear first lesson on index notation that tackles the 5 × 2 misconception head-on.

Math with Mr. J on YouTubechecked 2026-10-22

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