Use these targets, vocabulary, rubrics, examples, and score sheet with the instructor's approved lesson and procedure. This is an assessment companion, not a complete lesson or safety authorization.
By the end of the Fluids & Pressure unit, a student should be able to:
Five science criteria plus separately reported integration (Page 3).
Measure the buoyant force; compare to displaced fluid.
The student predicts float or sink and explains why (Page 4).
Weights, displaced volume, and buoyant force kept distinct.
You are making a decision, not adding up points. For each criterion, decide whether the work is Developing, Proficient, or Mastery — the column language tells you which. A criterion counts as mastered only when the student can both take the measurement and defend why it floats. Each student has three tokens per term; each token retries one rubric criterion. Approved accommodations, equipment failures, and approved absences are handled separately and do not consume these tokens.
Accept listed synonyms; use the distinction column to resolve near-matches.
| Canonical answer | Accepted synonyms | Common confusion / discriminator |
|---|---|---|
| Density & pressure | ||
| Density | mass per volume | A property of the material — not the same as total mass |
| Pressure | force per area | The same force on a smaller area is more pressure |
| Pressure with depth | hydrostatic pressure | Rises with depth because of the weight of fluid above |
| Pascal's principle | pressure transmits equally | Pressure on a confined fluid is passed on undiminished |
| Buoyancy & flow | ||
| Buoyant force | upward push of fluid | Equals the weight of the displaced fluid — not the object's weight |
| Archimedes' principle | displaced-weight rule | Floats if the displaced fluid weighs more than the object |
| Continuity | flow-rate conservation | Same flow rate — a narrower channel means faster flow |
| Bernoulli (qualitative) | fast flow, low pressure | Where a fluid speeds up, its pressure drops |
| Criterion | Developing | Proficient | Mastery |
|---|---|---|---|
| Density & pressure | Confuses mass with density or force with pressure. | Computes each but not how pressure changes with depth. | Relates density and pressure correctly and explains why pressure increases with depth in a fluid. |
| Buoyancy & Archimedes' principle | Thinks heavy things always sink. | States Archimedes' principle but cannot apply it to predict floating. | Predicts float or sink from the weight of displaced fluid and defends the reasoning quantitatively. |
| Pascal's principle | Does not see how pressure transmits through a fluid. | Knows a hydraulic lift multiplies force but not why. | Explains Pascal's principle and how a hydraulic system trades distance for force at equal pressure. |
| Fluid flow | Ignores that speed and area are related in flow. | Recalls that narrowing speeds flow but not the pressure consequence. | Applies continuity and the qualitative Bernoulli relationship to connect speed, area, and pressure in a moving fluid. |
| Lab technique (buoyancy measurement) | Estimates buoyancy by eye with no measurement. | Weighs an object in and out of water but does not compare to displaced volume. | Measures the buoyant force and the displaced fluid and verifies Archimedes' principle with uncertainty. |
| Integration (cross-domain) | Makes no supported connection between the source and the science. | Uses the source but needs help connecting evidence, writing, or limitations to the science. | Independently connects History, Reading, and Writing using a cited source, appropriate evidence, a limitation, and a scientific explanation. |
The split between Proficient and Mastery is displaced fluid: a mastered student explains floating by the weight of water pushed aside, not by “heavy” or “light.” Ask “how much water does it push aside, and what does that weigh?”
Read these before you grade. They show what Mastery and Developing actually sound like, plus the edge cases where you should coach rather than decide on the spot.
Student: ______________________________________ Date: _______________ Guide: _________________________
| # | Criterion | Decision | Notes |
|---|---|---|---|
| 1 | Density & pressure | Dev / Prof / Mast | |
| 2 | Buoyancy & Archimedes' principle | Dev / Prof / Mast | |
| 3 | Pascal's principle | Dev / Prof / Mast | |
| 4 | Fluid flow | Dev / Prof / Mast | |
| 5 | Lab technique (buoyancy measurement) | Dev / Prof / Mast | |
| 6 | Integration (cross-domain) | Dev / Prof / Mast |
☐ No ☐ Yes — for criterion: __________
Tokens left this term after this session (choose one): ☐ 3 ☐ 2 ☐ 1 ☐ None left
Dev = Developing · Prof = Proficient · Mast = Mastery · Unsure between two levels? Circle the lower one and note what a re-do would need.