Separate a mixture: a 40-minute 5th grade matter lab
What it is: a 5th grade matter lab where groups get a mixture of sand, salt, small paper bits and iron filings and must plan how to separate it using properties: magnetism, size, dissolving and evaporation. Students learn that mixtures keep the properties of their parts.
Time: about 40 minutes. Grade: 5th grade.
Materials: per group: a cup of mixture (sand, table salt, paper bits, a pinch of iron filings or steel paper-clip pieces), a magnet in a zip-top bag, a sieve or screen, water, a coffee filter and funnel, two clear cups, and a shallow dish.
- Show the mixture. Ask: "What's in here? How is each part different?" List properties.
- Groups write a plan: which tool for which part, and in what order.
- Groups follow their plan: magnet first (iron), sieve (paper bits), then add water to dissolve the salt and filter out the sand.
- Pour the salty water into a shallow dish and leave it by a sunny window. Check in 2 or 3 days for salt crystals.
- Groups compare plans and discuss which order worked best and why.
Safety: keep the magnet inside a bag so iron filings don't stick to it, wear safety goggles, never taste anything, and wash hands after the lab.
Differentiation: students who need support separate a two-part mixture first (sand and salt). Students who are ready explain the difference between a mixture and a solution with their results. English learners can use the words mixture, dissolve, filter, evaporate and magnet.
Quick check: ask a student how they would get salt back from salt water and why it works.
Save this activity to your library so it is ready when you need it.
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About this resource
- Shared by
- @UpOnlyLearning · Curriculum team
- Posted
- Oct 30, 2026
- Type
- Lesson plan
- Grade
- Grades 3–5
- Subject
- Science
- Language
- English
- License
- Free for classroom, co-op and tutoring use. Please don't resell.