A complete, no-prep 100-mark worksheet on classifying organisms using a classification key — ready to use for lessons, homework, or revision with KS3 Biology students aged 11-14.

Classification means sorting living things into groups based on their features. A key is a list of questions, each with two possible answers, that leads you to the right group.

Structured across three sections of progressive difficulty: Section 1 (30 marks) covers the seven levels of classification, the vertebrate groups and key terms through five multiple choice questions, a ten-statement true or false table and a ten-gap word bank task. Section 2 (40 marks) builds understanding through definitions, a table on the five vertebrate groups, using a key to sort five animals, and written explanations of why a penguin is a bird and a whale is a mammal. Section 3 (30 marks) challenges students with extended tasks: explaining why an armadillo is not a reptile, writing their own key for four animals, and explaining why correct classification helps to protect wildlife. A full answer key with detailed marking guidance is included. Comes as a PDF and an editable Word file (DOCX).

Also available: a companion extension pack with four enrichment activities, or save £1 with the complete lesson bundle — both listed on the iNewittAll TES store.

Google Classroom ready.

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