Earth & Space
Using and making a key — a chain of yes/no questions about features that identifies an animal.
⏱ Whole lesson ≈ 44 min · pick a tier in the bar, or leave on "All"
Recap of last lesson: vertebrates and invertebrates.
Vertebrate = has a ____.
How could you help a friend work out what an animal is, one question at a time?
A key = closed (yes/no) questions about features.
A classification key is a set of yes/no questions about an animal's features. Each answer sends you down a branch until you identify the animal. Good questions are closed — "Does it have fur?", not "How furry is it?"
A key uses ____ / no questions.
Turn “How big is it?” into a closed yes/no question.
Why must key questions be about features, not opinions?
Teacher models. Watch to recall the group features you'll ask about.
Swap the clip: change the ID after /embed/ (now HQdiSMUZEDA).
Walk an animal down a key together.
Backbone? → yes → Feathers? → no → Fur? → yes → mammal
Play the animation. Bust: open/opinion questions belong in a key.
Each question splits the animals into two — yes down one branch, no down the other.
Watch for: open questions ("how big?") and opinion questions ("is it cute?") that can't sort reliably.
Sort questions: would each one work in a key?
On your own. Sort each question, then build a short key.
Tap a card to sort it…
Sort the cards. Then finish: A key uses ____ questions.
Sort them, then write two good yes/no questions to sort animals.
Sort them, then make a short key that separates a bird, a fish and a spider.
Answer at your tier, then hand it in.
Why would a scientist use a classification key?