Summary
Mystery Doug takes on a real kid's question -- "Why were traffic lights invented?" -- and follows the clues. Traffic lights were invented as cities grew crowded, giving cars and people clear turns so the streets stayed safe. A quick five-minute watch to spark curiosity and kick off a conversation.
Viewer safety
All ages
Common Sense Media — not yet ratedIMDb Parents Guide — not yet rated
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Teaching resources
Discussion questions
Discussion
Doug investigates a question kids really asked: "Why were traffic lights invented?"
- What was Doug's answer to today's question, in your own words?
- What surprised you most about traffic, or what did you already know?
- What's one thing this makes you want to find out more about?
Quick work-a-long
Words to know: traffic, signal, safety.
Try it: Explain the answer to "Why were traffic lights invented?" to someone at home using these three words, then write down one new question it made you wonder.

