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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
Mastered Ready to learn LockedHover a node for its description · click to open
Computers in Everyday L…Computers in Everyday Life — frontier Identifying computers in everyday life — not just laptops but phones, tablets, smart speakers, traffic lights, washing machines; what makes something a computerReal-World RobotsReal-World Robots — locked What a robot really is — not the sci-fi version; robots in factories, robot vacuum cleaners, robot arms in surgery; that robots follow instructions given by peopleSmart Versus Not-Smart…Smart Versus Not-Smart Devices — locked Sorting objects into 'smart' (can sense and respond) and 'not smart' (just sits there); a toaster vs a smart speaker; introduction to the idea that some machines can sense and respond to the worldStep-by-Step Instructio…Step-by-Step Instructions — locked Step-by-step instructions for everyday tasks (making a sandwich, brushing teeth); that if instructions are wrong or missing, things go wrong; computers follow instructions exactly
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Mentally adding tens to 3-digit numbers

Mathematics · Addition & Subtraction · procedural

Mentally add and subtract a three-digit number and tens

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What mastery looks like

  • Calculate 345 + 40 mentally
  • Calculate 462 − 30 mentally
  • Explain that only the tens digit changes (unless bridging through a hundred)

Check your understanding

Can Mentally adding tens to 3-digit numbers quickly work out '354 + 40' or '628 − 30' in their head — knowing that only the tens digit changes?

Prerequisites

Required first

Unlocks (0 directly)

None.