Student learning · Grades 3–5 · 40 minutes
Garbage In, Garbage Out
Students write instructions for a classmate "robot" who follows them exactly, discover why vague prompts get surprising results, and build a recipe for clear prompts they can use with AI and with people.
Computer scientists have an old saying: garbage in, garbage out. If the instructions are unclear, the result will be too. In this game, a Director secretly draws a picture from a shape challenge and writes instructions, and a classmate Robot follows those words exactly, with no peeking and no questions. Round 1 results are often wildly off. Round 2, after the class builds a "prompt recipe," gets much closer. Students then upgrade vague AI prompts and learn the other half of the truth: even a great prompt can get a wrong answer, so people still check.
In this packet
- Handout A: Shape Challenge Cards (cut-apart cards)
- Handout B: Robot Instruction Sheet (worksheet)
- Handout C: Prompt Upgrade Lab (organizer)
- Facilitator key (last page)
TCEA ELE indicators
- AI1.1 I know how AI systems work and their capabilities in educational contexts.
- S5.1 I know how to approach complex problems systematically.
- S3.2 I can communicate my ideas clearly to others.
- S5.3 I am aware of how to apply computational thinking in various subjects.
- AI4.3 I am aware of strategies to develop AI-related problem-solving skills.
Full facilitator guide: mglearn.github.io/eles/activities/garbage-in-garbage-out.html
Handout A for Garbage In, Garbage Out
Shape Challenge Cards
Directors: draw your own picture using ONLY the shapes on the card. Keep it hidden. Then write instructions so your Robot can draw the same picture.
Challenge 1
Use exactly: 1 big square, 1 triangle, 1 small circle.
Challenge 2
Use exactly: 2 circles, 1 rectangle, 1 straight line.
Challenge 3
Use exactly: 3 triangles and 1 square.
Challenge 4
Use exactly: 1 big circle, 2 small circles, 1 curved line.
Challenge 5
Use exactly: 4 squares of different sizes. At least one must touch another.
Challenge 6
Use exactly: 1 rectangle, 2 triangles, 3 dots.
Challenge 7
Use exactly: 1 circle inside 1 square inside 1 triangle.
Challenge 8
Use exactly: 5 straight lines. They must make a letter of the alphabet, but you can't say which letter!
Handout B for Garbage In, Garbage Out
Robot Instruction Sheet
Director writes. Robot draws EXACTLY what the words say. No peeking, no questions, no pointing.
Round 1 · Director: write your instructions.
Round 1 · Robot: draw exactly what the words say.
Round 2 · Director: write your instructions using the Prompt Recipe.
Round 2 · Robot: draw exactly what the words say.
One thing I changed in Round 2 was ___. It helped because ___.
Even with a clear prompt, I still need to ___.
Handout C for Garbage In, Garbage Out
Prompt Upgrade Lab
Use the Prompt Recipe: Who is it for? What exactly? How many or how long? Which details? What style? Write what's missing, then upgrade the prompt.
| Garbage prompt | What's missing? | Upgraded prompt |
|---|---|---|
| Write a story. | ||
| Tell me about animals. | ||
| Make a poster. | ||
| Help me with math. | ||
| Explain why the sun goes around the Earth. | (Hint: check the facts in this prompt!) | |
Facilitator only for Garbage In, Garbage Out
Answer key and notes
Handout A: Shape Challenge Cards
- Challenge 1
- Common Round 1 problem: the Robot doesn't know where the triangle goes or how big anything is.
- Challenge 2
- Common problem: "put a circle next to it" (next to which side?).
- Challenge 3
- Common problem: triangles pointing different directions. Say which way the point faces.
- Challenge 4
- Common problem: "small" means different sizes to different people. Compare to something ("as big as a coin").
- Challenge 5
- Common problem: order. Tell the Robot which square to draw first.
- Challenge 6
- Common problem: counting and spacing of the dots.
- Challenge 7
- Common problem: the Robot draws the shapes side by side. Use the word "inside."
- Challenge 8
- Common problem: without the letter name, position and length words matter most.