This packet is everything a parent or guide needs to assess Unit 03 at home — learning targets, the answers that count as correct, the mastery rubric, calibration examples, and a clipboard score sheet. No multiple-choice test: the student shows mastery by running water-quality tests and tracing a cycle’s fluxes from the data aloud.
By the end of the Biogeochemical Cycles unit, a student should be able to:
Six criteria, each judged Not yet / Approaching / Mastered (Page 3).
Nitrate and dissolved O₂ measured, then tied to a cycle.
The student traces an atom through a cycle out loud (Page 4).
Test readings, flux estimate, and disruption claim 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 run the tests and justify what they reveal about the cycle. 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 |
|---|---|---|
| The four cycles | ||
| Carbon cycle | C cycle | Moves through photosynthesis, respiration, oceans, and fossil fuels |
| Nitrogen cycle | N cycle | N₂ gas is unusable until fixed; then nitrified and denitrified |
| Phosphorus & water cycles | rock / hydrologic cycles | Phosphorus is rock-bound (no gas step); water evaporates and precipitates |
| Stores, flows & disruption | ||
| Reservoir | pool; store | Where an element sits (atmosphere, ocean, soil, rock) — a store, not a flow |
| Flux | flow rate | The movement between reservoirs; humans have cranked several |
| Nitrogen fixation | N₂ → usable N | Biological (bacteria) or industrial (Haber–Bosch) |
| Eutrophication | nutrient over-enrichment | Fertilizer runoff feeds algae, then decomposition strips oxygen |
| Dissolved oxygen | DO | A water-quality reading; low DO signals heavy decomposition |
| Criterion | Not yet | Approaching | Mastered |
|---|---|---|---|
| The carbon cycle | Thinks carbon just sits in living things. | Names photosynthesis and respiration but misses the ocean and fossil reservoirs. | Traces carbon through photosynthesis, respiration, oceans, and fossil fuels, and explains how combustion adds to the atmosphere. |
| The nitrogen cycle | Cannot say why nitrogen gas is unusable to most life. | Names fixation but not the microbes or the industrial route. | Explains nitrogen fixation (biological and Haber–Bosch), nitrification, and denitrification, and how fertilizer floods the cycle. |
| The phosphorus & water cycles | Treats these cycles as identical to carbon’s. | Describes the water cycle but has no phosphorus reservoir in mind. | Contrasts the phosphorus cycle (rock-bound, no atmospheric step) with the water cycle and its evaporation–precipitation loop. |
| Reservoirs, fluxes & human disruption | Confuses a reservoir (a store) with a flux (a flow). | Labels reservoirs and fluxes but cannot quantify a change. | Distinguishes reservoirs from fluxes and predicts how a human input — combustion, fertilizer runoff — shifts a cycle out of balance. |
| Field technique (cycle-flux from data) | Cannot read a nitrate or dissolved-oxygen result from a test kit. | Records water-test data but cannot tie it to a cycle. | Runs water-quality tests (nitrate, dissolved O₂) and uses the readings to estimate a flux and infer human disruption. |
| 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 reading over recall: not just naming the reservoirs, but reading the nitrate and DO numbers as evidence of a disrupted flux. Ask what the readings imply about the human input upstream.
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 | The carbon cycle | NY / Appr / Mast | |
| 2 | The nitrogen cycle | NY / Appr / Mast | |
| 3 | The phosphorus & water cycles | NY / Appr / Mast | |
| 4 | Reservoirs, fluxes & human disruption | NY / Appr / Mast | |
| 5 | Field technique (cycle-flux from data) | 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.