A free 10–15 minute observation challenge with Detective Kee. Students compare two tilapia tanks, spot the warning signs and learn the difference between an observation and a diagnosis. Includes a printable activity, a teacher key and a short editable PowerPoint to introduce it to the whole class.

Farmer Milo has a worry: the fish in Tank B are not behaving like the fish in Tank A. Students join Detective Kee to look carefully, record the clues and decide what should happen next, without jumping to conclusions about disease.

What is included

• A printable fish-health observation activity (2 student pages, A4): an illustrated story with a two-tank comparison, three warning signs to record, an observation checklist and short reasoning questions
• A teacher key (1 page) with suggested answers, acceptable alternatives and a short science note
• A short editable classroom-introduction PowerPoint (5 slides, 16:9): a quick whole-class lesson starter that introduces observation, inference and diagnosis and sets up the activity. It is not a complete lesson and does not replace the printable activity. Teacher notes are included; no completed answers are shown.

Teaching time: about 10–15 minutes for the activity, plus a few minutes for the slide introduction.

Materials: the printable activity (pages 1–2 for students) and a projector for the slides. No lab equipment is needed.

Students are reminded throughout that warning signs are clues, not a diagnosis. No diseases are named and no water-quality data are used.

Suitable for KS3 and KS4 Biology and introductory aquaculture or land-based studies. These are suitability descriptions, not curriculum-alignment or endorsement claims.

PowerPoint compatibility: the slides use Fredoka and Nunito Sans. Google Slides includes both fonts; PowerPoint or Keynote may substitute fonts if they are not installed.

Want to investigate what might be happening inside the water? Continue with Kee’s Aquatic Science Mysteries, Case No. 002: The Mystery of the Invisible Poison.