Four White Powders
A 60-minute Grade 5 lesson on making observations and measurements to identify materials by their properties.
Four White Powders is a free 60-minute Grade 5 science lesson plan for Common Core standard 5-PS1-3 — identify a material by its properties. It is timed across 5 sections, gives the exact wording to use where the wording carries the mathematics, names 3 misconceptions with the teaching move that addresses each, and ends with an exit ticket and a printable worksheet with its answer key.
- Grade:
- Grade 5
- Length:
- 60 minutes
- Standard:
- 5-PS1-3
Grade 5 · Physical Science
5-PS1-3
Make observations and measurements to identify materials based on their properties.
Objective
Students will be able to identify unknown materials using a set of property tests.
Students are successful when they can
- Runs the same tests on every sample.
- Uses more than one property to identify.
- Says when the tests are not enough to decide.
What you need
- Four labelled white powders, water, vinegar, spatulas, hand lenses
- A results grid with a row per powder and a column per test
- The printable practice sheet linked at the end of this plan
The lesson
Warm-up
5 min- Show four identical-looking white powders and ask how they could be told apart.
- Rule out tasting.
Teach — one test is never enough
15 min- Run the dissolving test on all four. Two dissolve, two do not.
- Ask whether that identifies anything. It halves the field and no more.
- Run the vinegar test. Only powder C fizzes.
- Fill the grid and read across each row: each powder has a unique combination.
- Say the principle: identification comes from a set of properties, not one.
- Add the honest limit: two samples with identical results may be the same material.
“What does that test rule out, and what is still open?”
Investigate — identify four unknowns
22 min- Groups run four tests on four unknown powders, same amount each time.
- They complete the grid and look for unique rows.
- They identify what they can and say what remains undecided.
- They design a fifth test that would settle anything still open.
Independent practice
15 min- Students complete the 'Four White Powders' page.
- Check answers use more than one property.
Close
3 min- Ask which single test was most useful, and why.
What goes wrong, and why
Each of these is a reasoning error rather than carelessness. The fix addresses the reasoning.
Identifies from one test.
Why: It gave a clear result.
Fix: Two powders both dissolved. It separated nothing on its own.
Uses different amounts of each powder.
Why: A spoonful is a spoonful.
Fix: Fair comparison needs the same amount. A big sample fizzes longer.
Assumes a unique result means a known substance.
Why: It stood out.
Fix: It is distinguishable, which is not the same as identified.
If they are not there yet
- Two powders and two tests.
- A grid with the first row completed.
If they finish early
- Add a fifth unknown that duplicates another and see whether the tests catch it.
- Design a test using a property not yet used.
- Say what makes a property useful for identification.
Exit ticket
Two powders both dissolve in water. What does that tell you, and what would you do next?
What to look for: It does not separate them, so run a different test such as the vinegar test. Naming one as identified means the one-test limit needs another run.
Printable practice for 5-PS1-3
Free to print and copy, answer key included. Each sheet can generate a fresh set of problems for a retake.
- Four White PowdersCircle the best answer.
Questions about Four White Powders
How long does the Four White Powders lesson take?
60 minutes, split across 5 timed sections: warm-up 5 min, teach 15 min, investigate 22 min, independent practice 15 min, close 3 min. The minutes are stated per section and add up to the stated length, so the plan can be cut or extended at a section boundary rather than abandoned halfway.
Which standard does Four White Powders teach?
5-PS1-3 — 5-PS1-3, Physical Science for Grade 5: “Make observations and measurements to identify materials based on their properties.” In plain terms, identify a material by its properties.
What do I need to teach this lesson?
Four labelled white powders, water, vinegar, spatulas, hand lenses, a results grid with a row per powder and a column per test and the printable practice sheet linked at the end of this plan. Everything listed is either ordinary classroom equipment or a free printable from this site — there is nothing to buy and nothing to prepare beyond photocopying.
What mistakes should I expect in this lesson?
Three, each a reasoning error rather than carelessness: identifies from one test; uses different amounts of each powder and assumes a unique result means a known substance. The plan gives the thinking behind each one and the teaching move that addresses the thinking rather than the symptom.
How do I know whether the lesson worked?
The exit ticket asks: “Two powders both dissolve in water. What does that tell you, and what would you do next?.” It does not separate them, so run a different test such as the vinegar test. Naming one as identified means the one-test limit needs another run. That tells you whether the class needs a reteach or a thirty-second conversation before you plan tomorrow.
Is there a worksheet to go with Four White Powders?
Yes — 1 printable 5-PS1-3 worksheet, linked at the end of the plan and free like the rest of the site. Each one comes with an answer key and 25 versions, so the practice after the lesson can be a different paper on every desk.
Is Four White Powders free to use?
Yes. The plan, its printables and their answer keys are free to read, print and photocopy for your own class, with no account and no email capture. It was last reviewed on 8 September 2026. Please do not resell it or republish it as your own.
Last reviewed 2026-09-08. Aligned to 5-PS1-3 of the Next Generation Science Standards.