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A3 How Machines Learn

How do we know if an AI is any good?

Lesson plans ready, classifier tool in development

Stage
Creators, ages 9 to 11
Lessons
7 × 45 minutes (5.25 hours)
Ends with
A mini AI project and a one-page “how it works and where it fails”
Before you start
A2, or experience with block coding and simple data in a spreadsheet

Lesson plans ready, classifier tool in development. Lessons 1, 2, 5 and 6 work with cards and discussion today. Lessons 3 and 4 use the classifier tool, which is still being built; until then, build the classifier from sorted drawing cards and a tally sheet.

For children to do on their own. Every lesson has a step-by-step do-it-yourself version with a self-check. Open the kids’ version.

By the end, children can say

  • I can explain the difference between a program with rules and a model that learns.
  • I can explain why a model must be tested on examples it has not seen.
  • I can build and test a classifier with my own data.
  • I can calculate accuracy and describe what kinds of mistakes a model makes.
  • I can use simple checks to judge whether something online is reliable or computer-made.
  • I can present my AI project, say where it can fail and describe how I would use AI responsibly.
  • I can plan an AI helper for a good cause and say who is responsible and whose values it should respect.

About this course

Format. Classifier tool plus simple tally tables. Some lessons work with cards alone.

Tools. The classifier tool and a spreadsheet or table for tallying results. The tool is in development.

Key words. rule, pattern, training data, test data, accuracy, error, bias, source.

Curriculum tags.

  • Computer science: data and algorithms
  • Digital literacy: evaluating content and sources

The current national curriculum does not mention AI by name, so each course is tagged to the strands it supports.

Lesson plans

Open a lesson to see the steps. Printing this page opens them all.

Lesson 1: Rules Versus LearningI can explain the difference between a program with rules and a model that learns.
  1. Starter (5 min). Write rules for telling a cat from a dog. Where do they break?
  2. Teach (10 min). A rule-based program checks fixed rules; a learning model finds patterns in many examples.
  3. Activity (22 min). Sort mystery cards using made-up rules, then using examples, and compare which works better when something new appears.
  4. Reflect (8 min). Which approach would you choose for spam email? Why?

Do-it-yourself version for children

Lesson 2: Training and Testing DataI can explain why a model must be tested on examples it has not seen.
  1. Starter (5 min). A student who memorises answers versus one who understands: how can we tell?
  2. Teach (10 min). Split the data: a training set to learn from, a test set to check.
  3. Activity (22 min). Split a card deck into training and test sets, train a partner, then test only on the unseen cards.
  4. Reflect (8 min). What would go wrong if we tested on the same cards we trained on?

The “Teach the machine” activity on the Try page uses exactly this idea: the machine is tested on the creatures you did not teach it.

Do-it-yourself version for children

Lesson 3: Build a ClassifierI can build and test a classifier with my own data.
  1. Recap (5 min). Training and test data.
  2. Demo (8 min). Choose a question (for example, “is this a drawing of a happy or a sad face?”) and gather examples from the class.
  3. Build (25 min). Train the classifier with at least 20 examples per class, hold back 5 for testing, and record the results.
  4. Reflect (7 min). Which examples confused it?

Do-it-yourself version for children

Lesson 4: Accuracy and MistakesI can calculate accuracy and describe what kinds of mistakes a model makes.
  1. Starter (5 min). If 8 out of 10 test items are right, what is the accuracy? Is 80% good enough for a medical test?
  2. Teach (10 min). Accuracy as a fraction; two kinds of mistake (a false alarm and a miss).
  3. Activity (22 min). Record a tally of right, false alarm and miss for the classifier from Lesson 3, then improve the training set and retest.
  4. Reflect (8 min). Which mistake is worse for a smoke alarm, a false alarm or a miss?

Do-it-yourself version for children

Lesson 5: Real, Fake or Made-up?I can use simple checks to judge whether something online is reliable or computer-made.
  1. Starter (5 min). Two pictures, one real and one computer-made. Can you tell?
  2. Teach (10 min). Computers can make convincing pictures, text and voices. Check the source, look for the original, compare with other sources, and ask a trusted adult.
  3. Activity (22 min). Evidence detectives: examine pre-checked examples with a checklist (who made it, why, where else is it, does it feel too good or strange to be true?).
  4. Reflect (8 min). Three rules for checking before you share.

Teachers choose the examples in advance so children do not meet harmful or distressing content.

Do-it-yourself version for children

Lesson 6: Using AI WiselyI can present my AI project, say where it can fail and describe how I would use AI responsibly.
  1. Plan (8 min). A one-page template: what it does, how it was trained, how I tested it, where it fails.
  2. Build (25 min). Complete the project and the one-pager.
  3. Share (10 min). Peer review: “One thing it does well, one way it could fail.” Also ask: who checks it, and who is responsible if it is wrong?
  4. Reflect (7 min). Badge and a class “wise AI user” charter.

Do-it-yourself version for children

Lesson 7: AI for Good, AI with RulesI can plan an AI helper for a good cause and say who is responsible and whose values it should respect.
  1. Hook (7 min). Tell two short stories: AI that helps farms use less water, and AI that helps find people after a flood. Ask: who benefits, and who could be missed?
  2. Teach (8 min). AI is used for good in the environment, health and aid. Good use also needs rules: someone is responsible for it, it must treat people fairly, and it should respect the values and needs of the community it serves.
  3. Plan (22 min). In groups, plan an AI helper for one cause (saving water, finding lost pets, helping after a flood). On a planning sheet write: the data it learns from, one way it could be unfair or wrong, who checks it and whose values it should respect.
  4. Share (8 min). Each group presents in 1 minute. The class asks: who is responsible if it goes wrong?

Tool check: use the Ask Wondi activity, then look the same fact up in a book. Which was quicker? Which was easier to check? Discuss when each tool is best.

Do-it-yourself version for children

For grown-ups

  • Ask: “How do we know if an AI is any good?” and listen for “test it on new examples”.
  • Look at a picture or video together and play “real, edited or computer-made?” Check the source before deciding.
  • Ask which mistake matters more for a smoke alarm: a false alarm or a miss.

In every lesson: the “check it” habit

Who made this? What was it trained on? Where else can I check?