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Education Concept Tracker

A prerequisite knowledge graph of 1590 learning concepts across 8subjects. Track what you've mastered and see exactly what you're ready to learn next — the topics whose prerequisites you've already met. Built on the Marble Open Skill Taxonomy.

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Knowledge-graph map

Computing
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Numbers on a number line

Mathematics · Measurement · procedural

Solve word problems involving elapsed time by adding and subtracting time intervals in minutes, including using a number line

What mastery looks like

  • A film starts at 2:15 and lasts 47 minutes — when does it end?
  • Calculate how many minutes between 9:20 and 10:05
  • Use a number line to show the elapsed time between two events

Check your understanding

If Numbers on a number line starts football practice at 3:20 p.m. and it lasts 75 minutes, can they work out what time it finishes — using a number line to help?