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.
Student lessons, data, and public practice answers (not assessment keys): Unit 07 learning pathway.
The student demonstrates the following:
Five science criteria plus separately reported integration (Page 3).
Predict a balance point; verify it on a meter stick.
The student explains why a skater spins faster with arms in (Page 4).
Distances, torque balance, and result 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 predict the balance and defend it from the torques. 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.
| Term | Accepted explanation | Distinction |
|---|---|---|
| Torque | Moment of force; r F sin(angle) | State axis and direction, not just force magnitude. |
| Lever arm | Perpendicular distance to the force line | Not automatically the whole handle length. |
| Pivot | Chosen rotation axis | Inertia and torque must use the same axis. |
| Rotational equilibrium | Zero net torque about the axis | Complete static equilibrium also needs zero net force. |
| Rotational inertia | Resistance to angular acceleration | For point masses sum(m r^2); distribution matters. |
| Angular momentum | L = I omega in the stated model | Conserved only with zero net external torque about the same axis. |
| Angular velocity | Signed angular rate in rad/s | A smaller I does not guarantee spin-up without a condition on L. |
| Angular impulse | Signed torque-time area | Equals angular-momentum change, not a change in energy. |
| Rolling without slipping | v = R omega at fixed-surface contact | Check that available static friction supports the constraint. |
| Rotational kinetic energy | I omega^2 / 2 | Can change during inertia rearrangement even at fixed L. |
| Center of mass | Mass-weighted position | Coincides with center of gravity in a uniform field. |
| Criterion | Developing | Proficient | Mastery |
|---|---|---|---|
| Torque | Thinks only the size of the force matters, not where it acts. | Uses force times distance but ignores the angle or lever arm. | Calculates torque as force times lever arm, accounts for direction, and explains why a longer wrench is easier. |
| Rotational equilibrium & dynamics | Confuses balanced torque with balanced force or angular acceleration. | Uses a torque equation with incomplete axis or motion conditions. | Checks force and torque equilibrium; applies net torque = I alpha and radian kinematics for a fixed-axis, constant-inertia model. |
| Rotational inertia & rolling energy | Treats inertia as mass alone or ignores rotational energy. | Uses an ideal inertia but omits a rolling condition. | Calculates axis-specific inertia and rotational energy; checks the friction needed before using a no-slip rolling model. |
| Angular momentum | Does not recognize a rotational analog to momentum. | Names angular momentum but cannot apply conservation. | Uses same-axis angular impulse and L = I omega; states external-torque conditions and accounts for energy changes during inertia rearrangement. |
| Lab technique (balance / rotational inertia) | Balances by trial and error with no measurement. | Measures distances but does not predict the balance point first. | Uses a meter-stick balance to predict and then verify equilibrium, reporting the result 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 lever arm: a mastered student weighs distance as much as force. Ask “a small mass far out balances a big mass close in — why?”
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.
Evidence for the score sheet: Level: ______ Case/data: ______ Criterion: ______ Source/date: ______ Work/graph: ______ Assumptions/uncertainty: ______ Transfer: ______. Attach the independent attempt; practical observation is separate.
Student: ______________________________________ Date: _______________ Guide: _________________________
| # | Criterion | Decision | Notes |
|---|---|---|---|
| 1 | Torque | Dev / Prof / Mast | |
| 2 | Rotational equilibrium & dynamics | Dev / Prof / Mast | |
| 3 | Rotational inertia & rolling energy | Dev / Prof / Mast | |
| 4 | Angular momentum | Dev / Prof / Mast | |
| 5 | Lab technique (balance / rotational inertia) | 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.