Lesson 1095 of 1455
Reasoning Models: When AI Thinks Before It Speaks
OpenAI's o3, Claude with extended thinking, and DeepSeek-R1 actually pause and reason before answering. Slower, smarter, pricier.
Builders · Model Families · ~4 min read
The big idea
Reasoning models spend extra compute 'thinking' (generating internal reasoning tokens you may or may not see) before producing a final answer. They crush math, hard logic, and code — but cost more and take longer. Use them for problems where being right matters more than being fast.
Some examples
- A tough math contest problem → o3 or Claude extended thinking.
- A Codeforces-level coding challenge → DeepSeek-R1 or o3.
- A research synthesis comparing 20 papers → reasoning model with citations.
- A simple email reply → don't waste a reasoning model on it.
Try it!
Find a hard problem (logic puzzle, contest math). Try Claude or ChatGPT in normal mode and reasoning mode. Compare.
Key terms in this lesson
Practice this safely
Try this with a school, hobby, or family example where the stakes are low. Use the AI output as a draft you can question, not as the final answer.
- 1Ask AI to explain reasoning model in plain language, then underline anything that sounds uncertain or too broad.
- 2Give it one detail from "Reasoning Models: When AI Thinks Before It Speaks" and ask for two possible next steps plus one reason each step might be wrong.
- 3Check o3 against a trusted source, teacher, adult, expert, or original document before you use it.
End-of-lesson quiz
Check what stuck
8 questions · Score saves to your progress.
Lesson help
Questions are best handled with a grown-up here.
For this age range, Tendril keeps freeform AI chat paused until parent/guardian consent and child-safe moderation are fully verified. Use the quiz, notes, and related lessons below, or ask a parent, guardian, teacher, or librarian to work through the question with you.
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