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 reading real instruments and defending every number they write down.
By the end of the Measurement, Units & Significant Figures unit, a student should be able to:
Six criteria, each judged Not yet / Approaching / Mastered (Page 3).
Read real instruments and record what they show — watched live.
The student explains each number aloud (Page 4).
Readings, units, and averaged trials kept distinct.
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 take the measurement and defend the digits they kept. 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.
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 |
|---|---|---|
| Reading & units | ||
| Instrument | ruler, balance, graduated cylinder, stopwatch | Read at eye level, to the smallest mark |
| Unit | label on a measurement | A number without a unit means nothing |
| Metric conversion | changing metric units | mm ↔ cm ↔ m by powers of ten |
| Precision & honesty | ||
| Significant figures | sig figs | The digits the tool supports — not every digit the calculator shows |
| Precision | repeatability | How close repeated trials are, whether or not they’re right |
| Accuracy | closeness to true value | Can be precise but inaccurate |
| Repeat measurement | trials, then average | One reading is not the answer |
| Uncertainty | doubt in a measurement | Set by the smallest mark the tool offers |
| Criterion | Not yet | Approaching | Mastered |
|---|---|---|---|
| Reading instruments | Reads from an angle or guesses randomly between the marks. | Reads the right tool but looks from above the water line or rounds to the nearest big mark. | Reads ruler, balance, graduated cylinder, and stopwatch at eye level, to the smallest mark the tool offers. |
| Units & conversions | Writes bare numbers with no units. | Records units most of the time but stumbles converting within the metric system. | Attaches the correct unit to every measurement and converts cleanly between metric units. |
| Significant figures | Copies every digit the calculator shows, inventing precision the tool never had. | Senses the extra digits are wrong but keeps or drops them inconsistently. | Records exactly the digits the instrument supports — no invented precision, no thrown-away real digits. |
| Precision vs. accuracy | Uses “precise” and “accurate” as if they mean the same thing. | Can define both but cannot say which one a given set of results has. | Tells precision from accuracy and, shown a set of trials, says clearly which one the data shows. |
| Repeat measurement | Measures once and treats that single number as the answer. | Takes a few trials but reports only one, or averages them incorrectly. | Times the pendulum several times and reports the average, noting how close the trials were. |
| Integration (cross-domain) | Treats measuring as isolated; makes no connection to the anchor. | Mentions Semmelweis’s numbers but cannot link honest measurement to his death-rate comparison. | Connects honest counting and rate measurement to Semmelweis across History · Reading · Statistics and defends why honest numbers decide the case. |
The split between Approaching and Mastered is does the number mean what it says? Ask how many digits the tool really supports, and whether one reading is enough. Reading a tool is Approaching; defending the digits and the average is Mastered.
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.
Student: ______________________________________ Date: _______________ Guide: _________________________
| # | Criterion | Decision | Notes |
|---|---|---|---|
| 1 | Reading instruments | NY / Appr / Mast | |
| 2 | Units & conversions | NY / Appr / Mast | |
| 3 | Significant figures | NY / Appr / Mast | |
| 4 | Precision vs. accuracy | NY / Appr / Mast | |
| 5 | Repeat measurement | NY / Appr / Mast | |
| 6 | Integration (cross-domain) | NY / Appr / Mast |
☐ 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.