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 04 learning pathway.
The student demonstrates the following:
Five science criteria plus separately reported integration (Page 3).
Open the specimen and locate, name, and explain real structures — watched live.
The student explains why each structure does its job (Page 4 anchors).
Careful observations of the external and internal structures 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. Technique criteria are mastered only when an educator observes them; identification and explanation criteria can be mastered on the approved specimen, image, model, or virtual route without penalty. 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 |
|---|---|---|
| Shell / valves | the two halves (clam) | The hard outer covering; a clam’s two halves are its valves |
| Mantle | body wall | The tissue layer that secretes the shell and lines the cavity |
| Foot | muscular foot | The muscular organ for digging or anchoring; not a leg |
| Adductor muscles | shell-closing muscles | Hold the valves shut; cut them to open a clam |
| Siphons | incurrent / excurrent tubes | Draw water in and push it out; not the gut |
| Gills (ctenidia) | ctenidia | Feathery structures for gas exchange and filter feeding |
| Funnel | siphon (squid) | The squid’s jet nozzle; drives jet propulsion |
| Arms and tentacles | appendages (squid) | Squid has eight arms and two longer tentacles |
| Gut | digestive tract | The digestive tube; distinct from the feathery gills |
| Pen | gladius | The squid’s stiff internal support; reduced shell |
| Ink sac | ink gland | Stores ink the squid releases to escape |
| Beak | jaws (squid) | The hard mouthpart at the center of the arms |
| Homologous | similar through shared ancestry | Requires evidence such as structure, development, fossils, DNA, or a phylogenetic tree. |
| Analogous | similar function evolved separately | Function alone is not proof of shared recent ancestry. |
| Unresolved | not settled by these specimens alone | Use this category instead of forcing a claim. |
The split between Proficient and Mastery is the real specimen over the label: naming an organ from memory is not the same as pointing to it on the tray. Ask the student to find the gills and say what they do; the answer should match the feathery structure in front of them.
| Criterion | Developing | Proficient | Mastery |
|---|---|---|---|
| Instrument handling & safe technique | Forces the shell open or slashes through the mantle, destroying the soft parts inside. | Opens the shell or mantle with reminders but still cuts too deep and nicks the organs. | Holds each instrument the right way and opens the shell or mantle with shallow, controlled cuts that spare the soft parts; this technique criterion requires educator-observed approved practical work. |
| Careful exposure & observation of the mantle cavity | Tears into the mantle cavity and disturbs the organs before looking at them. | Opens the mantle cavity roughly but disturbs the gills or gut before observing their layout. | Opens the mantle cavity cleanly along the correct line and observes the arrangement of structures before disturbing anything; this exposure criterion requires observation. |
| Locating & naming external structures | Cannot point to the shell or mantle, the foot, or the siphons. | Finds a few external parts with prompting but confuses the foot, siphons, or (for a squid) the arms and tentacles. | Locates and names the external structures on the approved specimen, image, model, or virtual route: shell or valves, mantle, foot, siphons, or squid mantle, arms, tentacles, funnel, and eyes. |
| Locating & naming internal structures | Guesses at the organs or names the wrong ones once the specimen is open. | Finds the larger organs but cannot reliably distinguish the gills from the gut or trace the adductor muscles. | Locates and names internal structures on the approved route: gills, gut, adductor muscles, or squid pen, ink sac, and beak, stating when the route cannot show them. |
| Explaining structure & function (and specimen care) | Cannot say what a structure does, and lets the specimen dry out or handles it carelessly. | Explains one or two structures' functions but not the rest, and keeps the specimen moist only when reminded. | Explains structure and function with separate clam and squid proportions, and distinguishes homologous, analogous, and unresolved comparisons; handling care is observed separately. |
| 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 | Instrument handling & safe technique | Dev / Prof / Mast | |
| 2 | Careful exposure & observation of the mantle cavity | Dev / Prof / Mast | |
| 3 | Locating & naming external structures | Dev / Prof / Mast | |
| 4 | Locating & naming internal structures | Dev / Prof / Mast | |
| 5 | Explaining structure & function (and specimen care) | 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
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.
Dev = Developing · Prof = Proficient · Mast = Mastery · Unsure between two levels? Circle the lower one and note what a re-do would need.