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 02 learning pathway.
The student demonstrates the following:
Five science criteria plus separately reported integration (Page 3).
Measure the field of view, then size a specimen from it — watched live.
The student says why resolution and field of view matter more than raw power (Page 4).
Keep measurements distinct; complete the assigned calibration records.
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 justify why resolution and field of view matter more than raw power. 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 |
|---|---|---|
| Magnification | Image enlargement | A larger image is not automatically a clearer or better-resolved image. |
| Resolution | Ability to distinguish close points | Limited by optics, wavelength, numerical aperture and setup. |
| Field of view | Diameter of the visible circle | Must be calibrated for the setup before size estimates. |
| Empty magnification | Bigger image without new detail | Magnification beyond what the objective's numerical aperture can resolve: the image gets larger but shows no new detail. Thick-mount blur is a separate preparation problem. |
| Stage micrometer | Known scale slide | Used to calibrate the ocular scale or field for a specific objective. |
| Ocular micrometer | Eyepiece scale | Its divisions need calibration for each objective. |
| Numerical aperture | Light-gathering/resolving-power measure | Honors comparison; not a required purchase. |
The split between Proficient and Mastery is measurement over magnification: not just reading “400×”, but measuring the field and sizing what is in it. Ask “how wide is the field, and how much of it does the cell fill?”
| Criterion | Developing | Proficient | Mastery |
|---|---|---|---|
| Total magnification (ocular × objective) | Reads only the objective number and calls it the magnification, or cannot say where the two numbers come from. | Multiplies ocular by objective when reminded but forgets the ocular power or reads the wrong objective. | Reads the ocular and objective powers off the scope and states the total magnification for each objective on sight. |
| Magnification vs. resolution | Assumes the highest-power objective always gives the best view. | Knows resolution and field of view matter but still reaches for maximum power first. | Distinguishes enlargement from resolving power and states when extra magnification no longer adds usable detail. |
| Measuring field-of-view diameter | Cannot say how wide the field is at any objective. | Measures the field on low power but cannot work out the others. | Measures the field diameter against a ruler on low power and calculates it for each higher objective from the magnification change. |
| Estimating specimen size from the field | Guesses a specimen's size with nothing to compare it to. | Estimates size but ignores how much of the field the specimen fills. | Estimates a specimen's real size from the fraction of the known field it spans and reports it in sensible units. |
| Calibrating with a stage micrometer | Uses the eyepiece scale as if its marks were fixed distances. | Lines up the stage micrometer but cannot convert eyepiece units into real distance. | Calibrates the ocular or field measurement with a stage micrometer (observed), repeats readings, and reports an uncertainty rather than a single naked number. |
| 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. |
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 | Total magnification (ocular × objective) | Dev / Prof / Mast | |
| 2 | Magnification vs. resolution | Dev / Prof / Mast | |
| 3 | Measuring field-of-view diameter | Dev / Prof / Mast | |
| 4 | Estimating specimen size from the field | Dev / Prof / Mast | |
| 5 | Calibrating with a stage micrometer | 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.