๐Ÿ“‹ Teacher Cheat Sheet โ€” Session 6: Correlation vs. Causation

Data Science for Young Minds ยท Grade 5 ยท Ages 10โ€“11
~60 min Ages 10โ€“11 Session 6 of 8 ND-Friendly
โฑ Session Agenda
TimeBlockWhat's Happening
0โ€“5๐ŸŽฏ Hook"Ice cream sales and drowning rates both go up in summer. Does ice cream cause drowning?" (Take votes.)
5โ€“18๐Ÿ“– Lesson 1โ€“2Correlation defined ยท Causation defined ยท The difference ยท Confounding variables explained
18โ€“40๐Ÿ”ฌ Activity4 Spurious Correlations โ€” students explain the real relationship for each; then apply to serious examples
40โ€“50๐Ÿ“– Lesson 3How to argue from evidence responsibly ยท Claim-Evidence-Reasoning framework ยท Real scientific examples
50โ€“56๐Ÿง  Brain BreakThumbs up/down: "Correlation or Causation?" rapid-fire examples
56โ€“60โœ๏ธ CloseStudents write one C-E-R argument about a topic they choose. Preview S7.
Tone note: Funny examples lower anxiety. Students learn better when they feel safe being wrong. Start with ice cream/drowning; move to serious examples only after the concept is secure.
๐Ÿ“ฆ Materials Needed
Worksheets (1 per student) Spurious correlation cards (printed or projected) Pencils C-E-R framework posted on board
๐Ÿ’ก C-E-R Framework to post: Claim (what you think is true) โ†’ Evidence (data that supports it) โ†’ Reasoning (why the evidence supports the claim)
๐Ÿ“š Key Vocabulary
Correlation โ€” two variables tend to change together (both go up, or one up/one down)
Causation โ€” one variable directly causes the change in another
Confounding variable โ€” a hidden third factor that explains why two unrelated things correlate
Spurious correlation โ€” a correlation that exists but has no real causal relationship
Evidence โ€” data or observations that support a claim
Claim โ€” a statement about what is true, based on evidence

๐Ÿฆ The 4 Spurious Correlations โ€” Full Instructor Guide
1. Ice cream sales & drowning rates
Both rise in summer, fall in winter. Real connection: hot weather (confounding variable). People swim more when it's hot โ†’ more drownings. People eat more ice cream when it's hot. Ice cream doesn't cause drowning.
Detective question: "Is there something else that's high in summer that explains both?"
2. Nicolas Cage movies & pool drownings
A real (and famous) spurious correlation from the internet. Both rise and fall together over time โ€” pure coincidence. Real connection: none. Confounding: random variation in yearly data over small samples.
Use this to show how real the problem can look with charts. "The graph looks convincing โ€” but there's no possible mechanism."
3. Shoe size & reading ability (in children)
Older children have bigger feet AND read better. Real connection: age (confounding variable). Age drives both. A 10-year-old reads better than a 6-year-old AND has bigger feet โ€” not because of feet.
Good example for students: "Would putting bigger shoes on a 6-year-old help them read?" Obviously no โ€” the real cause is age/development.
4. Countries with more TVs per capita have higher life expectancy
Real connection: wealth (confounding variable). Wealthier countries have both better healthcare (โ†’ longer life) AND more TVs. TVs don't cause longer life. Buying everyone a TV wouldn't help.
This is a more serious example โ€” good bridge to medical/policy claims where the stakes are real.
Key teaching move: After each example, ask "What is the confounding variable?" Then: "How would we test whether this is truly causal?" (We'd need a controlled experiment โ€” hold everything else constant and change only the variable in question.)

๐Ÿ’ฌ Discussion Questions + Teacher Notes
  • "Ice cream doesn't cause drowning โ€” so what does?"
    โ†’ Hot weather (the confounding variable) causes both ice cream sales to rise AND more swimming (โ†’ more drownings). This is the classic example. Make sure students can name the confounding variable, not just say "it's wrong."
  • "If two things are correlated, can we be totally sure one doesn't cause the other?"
    โ†’ Not just from correlation alone. You need a controlled experiment (changing only one variable) to test causation. Real scientists use randomized controlled trials (RCTs) for exactly this reason.
  • "How could a politician misuse a correlation?"
    โ†’ "Cities with more police have more crime โ€” so police cause crime!" (In reality, high-crime cities hire more police.) Direction of causation can also be backwards. This is called reverse causation.
  • "What would it take to prove that exercise CAUSES better grades?"
    โ†’ A controlled experiment: randomly assign students to exercise vs. no-exercise groups, keep everything else identical, measure grades. Just correlating exercise habits with grades doesn't prove causation because many confounders exist (family income, school quality, etc.).
๐Ÿ“ C-E-R Framework โ€” Arguing from Evidence
Post this on the board and refer to it throughout the session. Grade 5 students should start using this structure for all data-based arguments.
C โ€” CLAIM: Make a clear statement about what you think is true.
"Ice cream sales do not cause drowning."
E โ€” EVIDENCE: Cite specific data that supports your claim.
"Both ice cream sales and drowning rates peak in July when temperatures are highest."
R โ€” REASONING: Explain why the evidence supports the claim โ€” name the mechanism.
"Hot weather causes both increased swimming activity (โ†’ drowning risk) and increased ice cream consumption. The confounding variable is temperature, not ice cream."
Watch for: Claims without evidence ("I just know"), evidence without reasoning ("the data shows it"), and reasoning that assumes causation from correlation.

๐ŸŽฏ Opening Hook
Write on board: "Ice cream sales and drowning rates both go up every summer. Does ice cream cause drowning?"
Take a vote: Yes / No / Complicated. Accept all answers without judgment.
โ†’ Most students will correctly say No โ€” but ask: "How do you know? What's actually going on?" This is the lesson: naming the confounding variable.
๐Ÿง  Brain Break
Thumbs up/down rapid-fire:
"Correlation or Causation?"
  • Smoking โ†’ lung cancer (Causation โ€” proven by controlled studies)
  • Shoe size โ†’ reading level in children (Correlation โ€” confounded by age)
  • Vaccination โ†’ reduced disease rates (Causation)
  • Countries with more chocolate consumption โ†’ more Nobel Prizes (Correlation โ€” wealth confounds)
๐Ÿง  ND-Friendly Tips
  • Funny first, serious second โ€” Ice cream/drowning and Nicolas Cage/drowning reduce the stakes. Once students feel safe, the serious examples (medical, political) land better.
  • Concrete question for each example โ€” Always ask: "What is the confounding variable?" This gives students a consistent scaffold for every new example.
  • C-E-R posted and visible โ€” Students with working memory difficulties need the framework externally visible throughout the writing portion.
  • Validate "it's confusing" โ€” Correlation vs. causation errors are made by professional researchers. Acknowledge the difficulty explicitly.
  • Peer argument sharing โ€” Students who struggle with writing can share their C-E-R verbally before writing. Oral rehearsal supports written output.