Lesson Exemplar — Science 6
Term 1 · Week 3 · Day 1 · Domain: Materials
This is one day. For the whole of Week 3 in the format DepEd prescribes for filing, see
lesson-plan-ilaw.md.
| Learning Area | Science |
| Grade Level | Grade 6 |
| Term | Term 1, Week 3 |
| CG source | Quarter 1, competency 3 (p. 41) |
| Lesson Title | Can You Get It Back? |
| Duration | 45 minutes |
| Medium of instruction | English |
| Format | MATATAG Lesson Exemplar (DepEd) — not ILAW, see above |
I. CURRICULUM CONTENT, STANDARDS, AND LESSON COMPETENCIES
A. Content Standards
Quoted from the curriculum guide (DepEd, August 2023, p. 41), Grade 6 Quarter 1, content standard 2:
Changes in materials can be either reversible or irreversible.
B. Performance Standards
By the end of the Quarter, learners use the words reversible and irreversible to describe changes to materials. They use diagrams and flowcharts to describe changes of state.
C. Learning Competency
CG Quarter 1, competency 3:
explain why physical changes are reversible, and chemical changes are irreversible.
Note the verb. The competency is not identify and not classify — it is explain why, and a learner who sorts twenty examples correctly without being able to say why has not met it.
By the end of the session, learners can:
- explain that a physical change is reversible because the material is still there;
- explain that a chemical change is irreversible because the original material has been used up;
- give evidence, not just a label, for a change they are shown; and
- state that the deciding question is is it the same material? rather than can I undo it?
D. Key Vocabulary
| Word | Meaning as used in this lesson |
|---|---|
| Reversible | Can be returned to what it was, because the material never stopped being that material. |
| Irreversible | Cannot, because the material is no longer there to return. |
| Physical change | The material is rearranged — melted, dissolved, torn, evaporated. |
| Chemical change | Materials are used up and different ones appear. |
| Evidence | The observation that supports the label. Not the label itself. |
The class sentence, said in §D and printed on the wall chart: "Not 'can I undo it' — 'is it still the same material?'"
E. Integration Across Learning Areas
| Area | How it appears |
|---|---|
| EPP | Cooking is a sequence of deliberate irreversible changes. So is preserving food, and so is not preserving it. |
| Araling Panlipunan | Salt-making by evaporation is a Philippine coastal industry; the technique in Week 5 is somebody's livelihood. |
| Mathematics | Three trials and an average is Grade 6 data handling, and it is competency 9 here. |
| English | Reversible and irreversible differ by one prefix and by everything else. Ten seconds well spent. |
II. MATERIALS
Needed — no cost. A saucer or jar lid; salt; water; a spoon. A sheet of paper to tear. A candle if there is one, unlit. Chalk and a board.
Set up in minute four and do not mention again. The saucer of salt water goes on the sunniest windowsill in the room. It is read on Friday, not today.
Not used: anything that is lit, and no acid. The chemical-change examples are recalled from what learners have watched at home. Grade 6 does not need a flame to understand one.
In addition. slides.html slides 1–12 ·
worksheet.html · game.html Rounds 1–2 ·
wall-chart.html
III. TEACHING AND LEARNING PROCEDURE
A. Activating Prior Knowledge · 6 minutes
Slide 2. Say: "Four things happened this morning. Ice melted in a glass. Rice was cooked. A shirt dried on the line. A slice of mango turned brown."
Take a vote on each: "Could that be undone?" Write the counts on the board.
Then set up the saucer: stir a spoon of salt into half a glass of water in front of the class until it is completely clear, pour a little into the saucer, and put it on the windowsill. Say nothing about it. Somebody will ask; answer "we will come back to it on Friday" and move on.
Why it goes on the sill in minute four. The lesson's central claim — that a dissolved material is still there — is one a class can accept politely on Monday and not believe. On Friday it is not a claim, it is a saucer.
B. Establishing Lesson Purpose · 4 minutes
Slide 3. Read the competency out loud, and put the emphasis where the guide puts it:
"Explain why physical changes are reversible and chemical changes are irreversible."
Say: "You could already sort those four this morning. What you may not be able to do yet is say why. That is what the word 'explain' is doing in that sentence, and it is what today is for."
C. Developing and Deepening Understanding · 24 minutes
C1 · The two reasons · 7 minutes
Slides 4 and 5. Build both columns with the class rather than reading them out:
| Physical | Chemical | |
|---|---|---|
| What happened | The material was rearranged | The material was used up; new ones appeared |
| Why that matters | It is still there, so it can come back | It is gone, so there is nothing to bring back |
Say: "The reason is in the second row, not the first. Reversibility is a consequence, not a definition."
C2 · The two hard cases · 9 minutes
Sugar first. Slides 6 and 7. Say: "Sugar in water disappears completely. Nothing is left to see. Is that a new material?"
Take the vote. Most classes say yes. Do not correct — offer the evidence instead:
- Taste it. Still sweet. (Do not actually taste anything in a classroom; say what would happen.)
- Boil the water off and the sugar comes back, all of it.
- Point at the windowsill. "That is the same question, being answered slowly."
Then burning. Slide 8. Say: "Paper burns. Ash is left. Somebody always says the paper is still there, in the ash."
Ask them to imagine writing on it. Say: "Ash is one of the materials the fire made. So are the smoke and the gases you cannot see. The paper was used up."
Slide 9: the four signs of a new material. These are Grade 4 content used here as evidence rather than as a list to recite.
C3 · The case where the two tests disagree · 8 minutes
Slide 10. Say: "A glass is dropped and shatters. Can you get it back?"
Everyone says no.
Slide 11. "Was a new material made?"
Let the silence sit. Then: "Pick up any piece. What is it made of?" Glass. "Melt all the pieces down. What do you get?" Glass.
Slide 12. Say: "So the two tests disagree. Can I undo it says chemical. Is it a new material says physical. Shattering is a physical change, and the second question is the one that decides. The first is a good shortcut with a real edge, and you have just found the edge."
This is the eight minutes that make it a Grade 6 lesson. Grade 4 met physical and chemical change; the difference this year is that the learner can say which test is fundamental and which is a proxy.
D. Making Generalisations · 7 minutes
Slides 13–15. Say the class sentence together, twice:
"Not 'can I undo it' — 'is it still the same material?'"
Return to slide 2's four changes and take the vote again. Compare with the counts still on the board. Ask for the reason each time, not the label.
| This morning | Kind | The reason |
|---|---|---|
| Ice melted | Physical | Still water; freeze it |
| Rice cooked | Chemical | Cannot be returned to raw grain |
| Shirt dried | Physical | The water became a gas and is still water |
| Mango browned | Chemical | A colour change that will not wash off |
Hand out worksheet.html.
IV. EVALUATING LEARNING
A. Assessment · 4 minutes
Exit ticket, three lines:
- Why is dissolving reversible? Give the reason, not the word.
- Why is burning irreversible? Give the reason, not the word.
- A glass shatters. Physical or chemical, and which question did you use?
| Item | A good answer | What a wrong answer tells you |
|---|---|---|
| 1 | The sugar is still there; evaporate the water and it returns | Because it is physical is circular — the label is being used as the reason |
| 2 | The paper is used up; ash and smoke are new materials | Because you cannot undo it is the proxy, not the reason |
| 3 | Physical; the new-material question | Chemical is the diagnostic answer. It means the shortcut is being used as the definition |
Item 3 is the one that reads. Items 1 and 2 will be on the wall chart by Friday.
B. Teacher Reflection
- Did anybody spot the shattered-glass problem before slide 11? Name them. Noticing that two tests can disagree is the single most transferable move in this lesson.
- How many gave a circular answer on exit ticket 1 — because it is physical? That is the shape to watch for all year; it appears again in Quarter 2 with because it is a producer.
- Did the vote on the four morning changes move between §A and §D? If not, the reasons were supplied rather than built.
C. Enrichment and Remediation
| Who | What |
|---|---|
| Giving the label without a reason | worksheet-remediation.html tasks 1–2 — recover something first, name it second |
| Ready to move on | Ask about a burning candle. Melting wax and burning wick, at the same time, on the same object. Which parts are which, and how can they tell? |
| Not yet convinced dissolving is physical | Do not argue. Point at the saucer and wait until Friday. Then ask them to explain it to the class |
Anticipated Misconceptions
| # | The misconception | Where it shows | What to do |
|---|---|---|---|
| 1 | Burning is reversible — the ash is still there | §C2, game Round 1 | Ask them to write on the ash. Ash is one of the fire's products, not the paper |
| 2 | Dissolving is irreversible — the sugar disappeared | §C2, exit ticket 1 | The saucer on the windowsill. Do not argue on Monday; wait for Friday and let the salt argue |
| 3 | Any colour change means a chemical change | Worksheet A | Mixing blue and yellow paint makes green and nothing new was made. The sign is a colour change that will not wash off or separate |
| 4 | Melting and dissolving are the same thing | Worksheet B | Melting needs heat and involves one material. Dissolving needs a second material and happens at room temperature |
| 5 | If I cannot undo it, it is chemical | §C3, exit ticket 3 | The shattered glass. This is the lesson's diagnostic and it is not carelessness — it is a good rule meeting its edge |
| 6 | Cooking is physical because it is just heat | §D | Heat is the cause. The test is the product: fried egg cannot be returned to raw, and it smells different, which is a new material reaching the nose |
| 7 | Reversible means easy | §C3 | Melting an iron bar back into shape is reversible and needs a foundry. Reversible is about whether the material survived, not about effort |
If There Is No Electricity
Nothing here needs it. A saucer, salt, water, a spoon and a sheet of paper are the whole apparatus, and §III carries everything the slides say.
If there is no sunny windowsill, the saucer still works — it takes three days instead of one, which is why it goes out on Monday rather than Thursday.
Part of the E-turo MATATAG artifact set. Companion files:
syllabus.md · lesson-plan-ilaw.md ·
assessment.md · offline-activities.md