Lesson Exemplar — Science 7
Term 1 · Week 4 · Day 1 · Domain: Science of Materials
This is one day. For the whole of Week 4 in the format DepEd prescribes for filing, see
lesson-plan-ilaw.md.
| Learning Area | Science |
| Grade Level | Grade 7 |
| Term | Term 1, Week 4 |
| CG source | Quarter 1, competency 5 (p. 46) |
| Lesson Title | The Particles Do Not Change. Only Their Spacing Does. |
| 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. 46), Grade 7 Quarter 1, content standards 2 and 3:
The particle model explains the properties of solids, liquids, and gases and the processes involved in changes of state.
Diagrams and flowcharts are very useful in demonstrating and explaining the motion and arrangement of particles during changes of state.
B. Performance Standards
By the end of the Quarter, learners recognize that scientists use models to describe the particle model of matter. They use diagrams and illustrations to explain the motion and arrangement of particles during changes of state.
C. Learning Competency
CG Quarter 1, competency 5:
explain the changes of state in terms of particle arrangement and energy changes: a. solid → liquid → vapor, and b. vapor → liquid → solid.
By the end of the session, learners can:
- draw the arrangement, spacing and relative motion of particles in all three states, with the particles the same size in every drawing;
- describe each change of state as energy entering or leaving, and spacing increasing or decreasing;
- state that the particles themselves do not change size, number or kind; and
- say what is between the particles, and why it cannot be air.
D. Key Vocabulary
| Word | Meaning as used in this lesson |
|---|---|
| Particle | The smallest piece of a pure substance that is still that substance. Not a grain you can see. |
| Arrangement | Whether there is a pattern. |
| Spacing | How far apart. Solid and liquid are close; a gas is about ten times further. |
| Relative motion | Vibrating in place · sliding past · flying free. |
| Vapour | The gas state of something that is a liquid at room temperature. |
The class sentence, said in §D and printed on the wall chart: "Same particles. Different spacing. Different speed."
E. Integration Across Learning Areas
| Area | How it appears |
|---|---|
| Mathematics | Ten times the spacing is about a thousand times the volume. The cube is the point, and it makes the number believable. |
| EPP | Why a pressure cooker works, and why a sealed tin must never go on a fire. |
| MAPEH | Sweating is evaporative cooling, and it is the model's best everyday evidence. |
| English | Vapour, evaporate and steam are three different words and one of them is commonly used for all three. Worth thirty seconds. |
II. MATERIALS
Needed — no cost. Blank paper, one sheet per learner. A bottle of water. Chalk and a board. A coin for tracing circles the same size.
Useful and improvisable. A cold surface — a metal spoon kept in shade, a tile, a bottle from a cool place — for the condensation demonstration in §D.
Not used: a bunsen burner or a thermometer. Nothing here is heated in the room. Every change of state is either recalled or observed at room temperature, which is safer and loses nothing.
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
Hand out blank paper before saying anything.
Slide 2. Say: "Three boxes on one page. Draw the particles in ice. Draw the particles in liquid water. Draw the particles in steam. Four minutes."
Say nothing else. Do not tell them the particles should be the same size. Walk the room and look.
Why this is the first six minutes. Every misconception in this lesson will be on those pages, drawn by the class, before anybody has been taught anything. The lesson then dismantles the class's own drawings rather than a set of errors somebody else made, and the difference in how that lands is considerable.
Count roughly, without comment: how many drew the steam particles bigger? In most classes it is half.
B. Establishing Lesson Purpose · 4 minutes
Slide 3. Read the model's claims out as a list, one at a time:
All matter is made of tiny particles · each pure substance has its own kind · they are constantly in motion · they have spaces between them · they attract each other · they move faster as the temperature increases.
Say: "Those are six claims. Today we are going to use them to explain melting and boiling — and then we are going to see what they forbid. A model that forbids nothing explains nothing."
C. Developing and Deepening Understanding · 24 minutes
C1 · The three arrangements · 7 minutes
Slides 4 and 5. Build all three on the board, and use the same chalk circle size throughout — visibly, deliberately, so the class sees you keeping it constant:
| State | Arrangement | Spacing | Motion |
|---|---|---|---|
| Solid | Regular pattern | Touching | Vibrating in place |
| Liquid | No pattern | Still touching | Sliding past each other |
| Gas | No pattern | About ten times further | Fast and straight, until they hit something |
Say: "Ten times the spacing. What does that do to the volume?" Take the answer: about a thousand times. "That is why a small pan of water fills a kitchen with steam."
C2 · The four changes · 8 minutes
Slides 6, 7 and 8. Do all four, and for each one ask the same two questions before giving anything:
"Does energy go in or out? Does the spacing increase or decrease?"
| Change | Energy | Spacing | The thing to say aloud |
|---|---|---|---|
| Melting | In | Increases a little | The pattern breaks; they are still touching |
| Boiling | In | Increases enormously | They separate completely — that is why it takes more energy |
| Condensing | Out | Decreases | They slow enough for attraction to take hold |
| Freezing | Out | Decreases | They slow enough for the pattern to form |
Ask: "Which needs more energy for the same substance — melting or boiling?" Boiling, and the reason is in the spacing column, not in a number they have to remember.
C3 · The three denials · 9 minutes
Slide 9. Say: "Now the part that matters. A model earns its keep by ruling things out. Here are three things this model will not let you say."
Denial 1 — slide 10. The particles do not get bigger. Ask them to look at their own drawing from §A. Say: "If your steam circles are bigger than your ice circles, the drawing says the particles swelled. They did not. The substance expanded because they moved apart."
Do not single anybody out. Say instead: "About half of every class draws it that way, including mine when I was your age."
Denial 2 — slide 11. A single particle cannot melt. Say: "Melting is what a large number of particles do together when the pattern breaks. One particle has no state, the same way one person is not a queue."
Denial 3 — slide 12. There is nothing between the particles. Ask: "What is in the gaps?"
Somebody will say air. Ask: "What is air made of?" Particles. "And what would be in the gaps between those?"
Let the class reach the regress themselves. Say: "Nothing. Not air, not vapour, not anything. That is the hardest sentence in this lesson and it is the one the model actually says."
D. Making Generalisations · 7 minutes
Say the class sentence together, twice: "Same particles. Different spacing. Different speed."
Then the puddle — slide 14. Say: "A puddle dries at thirty degrees. Water boils at a hundred. So evaporation is not boiling. What is happening?"
Draw it out: the fastest particles at the surface escape, even when the average is far below boiling. And what is left behind has a lower average energy — which is cooler.
Say: "That is why sweat works. It is the best evidence for this model you will meet all year, and you have been carrying it around since you were born."
Hand out worksheet.html.
IV. EVALUATING LEARNING
A. Assessment · 4 minutes
Exit ticket, three lines:
- Water boils. Energy in or out? Spacing increases or decreases?
- Name one thing the particle model forbids.
- What is in the spaces between the particles of a liquid?
| Item | A good answer | What a wrong answer tells you |
|---|---|---|
| 1 | In; increases enormously | Out means the change has been read backwards; check the arrows on Day 2 |
| 2 | Particles cannot swell / cannot melt alone / no new particles from heating | A blank here means the model is being held as a picture |
| 3 | Nothing | Air is the diagnostic answer, and it is the most common one |
Items 2 and 3 are the ones that read. Item 1 is available from the wall chart.
B. Teacher Reflection
- What fraction of the §A drawings had bigger particles in the steam box? Record the number. It is the cleanest before-and-after measurement available in this topic — ask for the same three drawings again in Week 6 and compare.
- Did anybody reach the air is made of particles too regress unprompted in §C3? That is the single most sophisticated move available in this lesson.
- How many exit tickets said air on item 3? Whatever the number, plan Day 3 around it rather than treating it as a slip.
C. Enrichment and Remediation
| Who | What |
|---|---|
| Drawing the particles bigger in the gas box | worksheet-remediation.html tasks 1–3 — the class stands as the particles first, and nobody grows |
| Ready to move on | Water expands when it freezes, which the model appears to forbid. It is a real exception with a real explanation, and it is worth an afternoon |
| Still putting air in the gaps | Activity 2 in offline-activities.md runs the regress out loud, with learners as the particles inside the particles |
Anticipated Misconceptions
| # | The misconception | Where it shows | What to do |
|---|---|---|---|
| 1 | Particles get bigger when heated | §A drawings, worksheet A | Expansion is increased spacing. Trace every circle round the same coin and the error becomes impossible to make |
| 2 | There is air between the particles | §C3, exit ticket 3 | Ask what air is made of, then ask what is between those. The regress is the argument |
| 3 | Particles in a solid are still | Game Round 3 | They vibrate. Solid means the pattern holds, not that motion stops |
| 4 | A single particle melts | §C3 | Melting is a property of an arrangement, not of a particle. One person is not a queue |
| 5 | Compressing a gas makes it heavier | Game Round 3 | The same particles are in there. Mass unchanged, volume reduced |
| 6 | Particles are tiny visible grains of the substance | §C1 | A grain of salt contains an enormous number of particles. If you can see it, it is not one |
| 7 | Evaporation only happens at boiling point | §D | The puddle at 30 °C. This is also why the exit ticket asks about energy direction rather than about temperature |
If There Is No Electricity
Nothing here needs it. Paper, chalk, a board and a coin are the whole apparatus, and §III carries everything on the slides.
If there is no cold surface for condensation, skip the demonstration and use breath on a window or on a phone screen, which every learner in the room has already seen a hundred times and has never been asked to explain.
Part of the E-turo MATATAG artifact set. Companion files:
syllabus.md · lesson-plan-ilaw.md ·
assessment.md · offline-activities.md