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
The lesson
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.
Watch it
Where it sits
Where this leads
Jobs that lean on this skill. Follow one to see everything it is built on.
8 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.