This packet is everything a parent or guide needs to assess Unit 07 at home — learning targets, the technique that counts as correct, the mastery rubric, calibration examples, and a clipboard score sheet. No multiple-choice test: the student shows mastery by making a living wet mount and finding, tracking, and naming real organisms on a real scope.
By the end of the Microorganisms unit, a student should be able to:
Six criteria, each judged Not yet / Approaching / Mastered (Page 3).
Mount a live sample; find and track organisms.
The student names each organism on sight (Page 4).
Sample, organisms found, and a labeled sketch 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 hold a moving organism in view and name it while handling the culture safely. 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 |
|---|---|---|
| Making the mount | ||
| Living wet mount | fresh mount | A small drop under a coverslip, kept alive to move and view |
| Pond-water sample | culture drop | Draw from the bottom sediment where organisms gather |
| High power (40×) | high-dry objective | Needed to resolve bacteria and small protists |
| Culture hygiene | safe disposal | Handle and dispose of live cultures safely |
| What you find | ||
| Protist | single-celled eukaryote | Amoeba, paramecium, euglena — motile; chase with the stage |
| Algae | green cells / colonies | Recognized by chloroplasts; drift, not swim |
| Bacteria | prokaryotes | Tiny; classified by shape — rod, coccus, spiral |
| Debris | non-living particle | Drifts passively; not an organism — the key discriminator |
| Criterion | Not yet | Approaching | Mastered |
|---|---|---|---|
| Making a living wet mount | Uses too much water or crushes the coverslip so organisms wash away or die. | Mounts pond water but floods the slide, letting everything drift too fast to follow. | Draws a small drop from the bottom of the sample, mounts it under a coverslip, and keeps enough organisms alive and in view to observe. |
| Finding & tracking motile protists | Cannot spot a moving organism or loses it the instant it swims. | Sees something move but cannot follow it with the stage. | Locates and tracks a motile protist — amoeba, paramecium, or euglena — steering the stage to keep it in the field. |
| Recognizing algae | Cannot tell algae from other green material. | Suspects algae but cannot point to the feature that marks it. | Recognizes algae by their chloroplasts and form and separates them from plant debris in the mount. |
| Recognizing bacterial shapes | Cannot make out bacteria or tell one shape from another. | Sees tiny specks but cannot classify them as rod, sphere, or spiral. | Identifies bacterial shape — rod, coccus, or spiral — under high power and distinguishes it from stray particles. |
| Distinguishing organisms from debris & handling cultures safely | Calls every speck an organism and handles live cultures carelessly. | Tells some organisms from debris but is loose with culture hygiene. | Separates living, moving organisms from drifting debris and handles and disposes of live cultures safely. |
| Integration (cross-domain) | Treats the science as isolated facts; makes no cross-domain connection. | Names a link to history, reading, or writing but cannot defend why it matters. | Connects the unit to its anchor across History · Reading · Writing (plus chosen electives) and defends why the connection matters. |
The split between Approaching and Mastered is self-powered motion: an organism swims or crawls against the drift; debris just floats. Ask “is it moving on its own, or being carried?”
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 | Making a living wet mount | NY / Appr / Mast | |
| 2 | Finding & tracking motile protists | NY / Appr / Mast | |
| 3 | Recognizing algae | NY / Appr / Mast | |
| 4 | Recognizing bacterial shapes | NY / Appr / Mast | |
| 5 | Organisms vs. debris & culture safety | 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.