Classification Keys
Explore and use classification keys to identify, group, and name living things in local and wider environments
What a learner can do afterwards
- Follow a branching classification key to identify an unknown organism
- Create a simple yes/no classification key for a set of 6-8 organisms
- Use a key to identify organisms in the local environment during a field activity
1 · Read
You already know how to sort living things into groups. A classification key uses that idea to help you find the name of something you don't recognize. It asks one question at a time, and your answer decides which question comes next.
Zara finds a small creature under a log. The key asks: Does it have six legs? She says yes. Next question: Does it have a hard shell? She says yes. The key tells her it's a beetle.
Each question splits the living things into two smaller groups: yes or no. You follow your answers like a path through the key, until only one name is left.
To build your own key, pick a feature that splits your group evenly, like 'has wings' or 'has a shell'. Ask that first, then find a new splitting feature for each smaller group.
A classification key is a path of yes/no questions that leads you to a name.
2 · Watch
Take it off screen
Where it sits
This opens up
Where this leads
Jobs that lean on this skill. Follow one to see everything it is built on.
24 questions wait behind this lesson, each with its answer explained. Every answer feeds the sky: stars light as they are learned, and dim when it is time to come back.