Unit 03 · Chemical & Physical Changes — printable rubric packet

Bright Minds Physical Science · Course Pack

Chemical & Physical Changes — Unit Packet

Overview

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This packet is everything a parent or guide needs to assess Unit 03 at home — learning targets, the answers that count as correct, the mastery rubric, calibration examples, and a clipboard score sheet. No multiple-choice test: the student shows mastery by running a change, reading the evidence, and showing that mass is conserved.

Unit learning targets

By the end of the Chemical & Physical Changes unit, a student should be able to:

Tell a physical change from a chemical change, with everyday examples of each.
Name the signs of a chemical change — color change, gas, heat or light, a new solid.
Explain that a physical change alters form but not the substance (melting, tearing, dissolving).
Show that mass is conserved — the mass before a change equals the mass after.
Investigate an unknown change and defend whether it was physical or chemical from the evidence.

How this unit is assessed

Mastery rubric

Six criteria, each judged Not yet / Approaching / Mastered (Page 3).

Change investigation

Run a change, watch for the evidence, weigh before and after.

Oral check

The student defends physical or chemical from the evidence (Page 4).

Lab notebook

Observations, the mass check, and the conclusion kept distinct.

How to read a Bright Minds rubric

You are making a decision, not adding up points. For each criterion, decide whether the work is Not yet, Approaching, or Mastered — the column language tells you which. A criterion counts as mastered only when the student can both read the evidence and justify the physical science behind it. A student carries three tokens per term; one token buys a re-do of one criterion on another day, so a single bad afternoon never sinks the unit.

Chemical & Physical Changes · Vocabulary

Key Terms — What Counts as Correct

Vocabulary

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Accept any answer in the synonyms column — they are pre-approved as equivalent. The third column flags the confusions that look close but are not yet, so you can coach precisely.

Canonical answer	Accepted synonyms	Common confusion / discriminator
Kinds of change
Physical change	form changes, substance stays	Melting, tearing, dissolving — often reversible, no new substance
Chemical change	a new substance forms	Signaled by color, gas, heat/light, or a new solid; hard to reverse
Reaction	another word for a chemical change	Starting materials become new materials
Evidence of a chemical change
Color change	a new color appears	A sign of a chemical change — if nothing else explains it
Gas produced	bubbles or fizzing	A sign of a chemical change when no boiling is involved
New solid	a solid forms from liquids	Evidence of a chemical change; the solid wasn’t there before
What stays the same
Conservation of mass	mass before = mass after	Matter isn’t created or destroyed, only rearranged
Mass	how much matter	Measured on a balance; unchanged by a physical or chemical change
Closed system	sealed container	Nothing gets in or out — trapped gas still counts on the balance

Chemical & Physical Changes · Mastery Rubric

Six Criteria — Not yet / Approaching / Mastered

Rubric

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Criterion	Not yet	Approaching	Mastered
Physical vs chemical change	Calls any change a chemical change.	Defines the two but mislabels everyday examples.	Sorts changes as physical or chemical and defends each from what was observed.
Evidence of a chemical change	Cannot name a sign that a chemical change happened.	Names one sign but misses the others.	Names and spots the signs — color change, gas, heat or light, a new solid that won’t reverse.
Physical changes	Thinks melting or dissolving makes a new substance.	Names physical changes but cannot explain why the substance is unchanged.	Explains that melting, tearing, and dissolving change form only — the substance stays the same.
Conservation of mass	Expects mass to disappear when something burns or dissolves.	States that mass is conserved but cannot show it.	Measures mass before and after a change and shows it is conserved, accounting for any gas.
Lab technique (change investigation)	Runs the change with no measurement or record.	Observes the change but does not weigh or control it.	Investigates a change, records the evidence, and weighs before and after cleanly.
Integration (cross-domain)	Treats the science as isolated facts; makes no cross-domain connection.	Names a link to history, reading, or writing but cannot defend why it matters.	Connects the unit to its anchor across History · Reading · Writing (plus chosen electives) and defends why the connection matters.

What “Mastered” requires

The student decides physical or chemical and backs it with observed evidence, then shows mass held steady — unprompted.

What does not pass

Calling melting ice a chemical change is Not yet on criterion 1 — it’s still water, so the substance never changed.

Grading it at home

The split between Approaching and Mastered is evidence over guessing. “It looks different” isn’t enough. Ask “what did you see that tells you a new substance formed?” Naming the sign — color, gas, heat, a new solid — is where Mastered begins.

Chemical & Physical Changes · Calibration

Anchor Exemplars — To Calibrate Your Ear

Anchors

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Read these before you grade. They show what Mastered and Not yet actually sound like, plus the edge cases where you should coach rather than decide on the spot.

Physical vs chemical change

▶ Mastered

“The steel wool got heavier and changed color when it burned — that’s a new substance, a chemical change. Melting the wax was physical; it’s still wax, just softer. The test is whether new stuff formed.”

▶ Not yet

“Burning and melting are both just heat changing things.” (No line between physical and chemical.)

Integration — Lavoisier & conservation of mass

▶ Mastered

“Lavoisier sealed the jar and weighed it before and after — the mass stayed the same even though the stuff changed. That’s why I know the mass I start with should equal the mass I end with, even after a chemical change.”

▶ Not yet

“Lavoisier was a famous scientist.” (No link to conservation of mass.)

Edge cases — coach, don’t fail

▶ Change with no evidence

“It’s chemical because it looks different.” Coach toward specific evidence — color, gas, heat, a new solid. Approaching until they name the sign.

▶ Mass seemed to vanish

Burns a candle and says mass disappeared. Coach: the gas carried mass away — in a sealed jar the mass holds. Fixable.

Chemical & Physical Changes · Score Sheet

Unit Score Sheet — One per student

Score Sheet

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Student: ______________________________________ Date: _______________ Guide: _________________________

Mastery criteria — circle one per row

#	Criterion	Decision
1	Physical vs chemical change	NY / Appr / Mast
2	Evidence of a chemical change	NY / Appr / Mast
3	Physical changes	NY / Appr / Mast
4	Conservation of mass	NY / Appr / Mast
5	Lab technique (change investigation)	NY / Appr / Mast
6	Integration (cross-domain)	NY / Appr / Mast

Change investigation — technique check

Starting materials described and weighed before the change.
Change carried out and the signs of a chemical change watched for.
Evidence recorded — color, gas, heat or light, or a new solid.
Mass measured after and compared, accounting for any gas.
Notebook keeps observation separate from the physical-or-chemical conclusion.

Token used this session?

☐ No ☐ Yes — for criterion: __________ Tokens remaining: ☐ 3 ☐ 2 ☐ 1 ☐ 0

NY = Not yet · Appr = Approaching · Mast = Mastered · Unsure between two levels? Circle the lower one and note what a re-do would need.