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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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Fluent adding and subtracting within 100

Mathematics · Addition & Subtraction · procedural

Fluently add and subtract within 100 using strategies based on place value, properties of operations, and the relationship between addition and subtraction

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What mastery looks like

  • Add two-digit numbers within 100 efficiently (e.g. 46 + 37 using place-value partitioning)
  • Subtract two-digit numbers within 100 fluently (e.g. 83 − 25)
  • Choose between strategies (decomposing, compensating, using known facts) based on the numbers involved

Check your understanding

Can Fluent adding and subtracting within 100 reliably add or subtract two-digit numbers like '68 + 27' or '91 − 45', choosing the best strategy for each problem?

Prerequisites

Required first

Unlocks (6 directly)