This packet is everything a parent or guide needs to assess Unit 01 at home — the 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 the lab and reasoning from the plate-tectonic evidence aloud.
By the end of the Earth's Structure & Plate Tectonics unit, a student should be able to:
Six criteria, each judged Not yet / Approaching / Mastered (Page 3).
Epicenter located from three seismograms and a plate-boundary map read — done at the bench.
The student reasons from the plate-tectonic evidence aloud (Page 4 anchors).
Contemporaneous record of seismogram readings, the epicenter solution, and boundary calls.
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 technique and justify the geology behind it. 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 |
|---|---|---|
| Earth's interior | ||
| Crust | outermost solid layer; oceanic / continental | Thin; part of the lithosphere, not the same thing as it |
| Mantle | layer below the crust; solid rock | Flows plastically over time (asthenosphere) — not liquid |
| Core | solid inner + liquid outer iron-nickel | Source of Earth's magnetic field; not molten all the way up |
| Lithosphere | rigid crust + uppermost mantle | A mechanical layer (behavior), not a compositional one |
| Plate boundaries & motion | ||
| Asthenosphere | weak, slowly flowing upper mantle | Plates ride on it; “plastic,” not molten |
| Divergent boundary | plates move apart; new crust forms | Mid-ocean ridges, rift valleys — building, not destroying |
| Convergent boundary | plates collide; subduction or uplift | Trenches, mountains, deep quakes, volcanic arcs |
| Transform boundary | plates slide past each other | Crust neither made nor destroyed; shallow quakes (San Andreas) |
| Evidence & hazards | ||
| Seafloor spreading | new ocean floor forms at ridges | The mechanism Wegener lacked; makes symmetric magnetic stripes |
| Paleomagnetism | fossil magnetism frozen into rock | Records past pole positions; stripes mirror across a ridge |
| Epicenter | surface point above the focus | Not the focus — that is underground at the actual rupture |
| P-wave / S-wave | primary (fast) / secondary (slower) | Arrival gap gives distance; S-waves cannot cross the liquid outer core |
| Criterion | Not yet | Approaching | Mastered |
|---|---|---|---|
| Earth's internal structure | Confuses the layers or thinks the whole interior is molten. | Names crust, mantle, and core but blurs composition layers with mechanical ones. | Distinguishes crust/mantle/core by composition and lithosphere/asthenosphere by behavior, and explains how we know (seismic waves). |
| Plate boundaries & motion | Cannot name the boundary types or thinks continents are fixed. | Names divergent, convergent, and transform but mixes up what each produces. | Predicts the landforms, earthquakes, and volcanism at each boundary type and gives a real-world example of each. |
| Evidence for plate tectonics | Treats plate tectonics as something to accept on authority. | Lists one line of evidence but cannot connect it to a mechanism. | Marshals matching coastlines/fossils, seafloor spreading, and paleomagnetism into the case that vindicated Wegener. |
| Earthquakes & volcanoes | Sees earthquakes and volcanoes as random or unrelated to plates. | Links them to plates in general but not to specific boundaries. | Explains where and why quakes and volcanoes cluster, and reads P- and S-wave arrivals to locate a quake. |
| Lab technique (triangulation / maps) | Cannot read a seismogram or a plate-boundary map. | Reads the traces but misplaces the epicenter or the boundary. | Triangulates an epicenter from three seismograms and interprets a plate-boundary map, defending each call. |
| Integration (cross-domain) | Treats the science as isolated facts. | Names a link to history, reading, or writing but cannot defend it. | Connects the unit across History · Reading · Writing and defends why it matters. |
Work down the criteria one at a time. Ask the student to reason it out rather than recall — “why is there a line of volcanoes behind the Andes?” The cause (an oceanic plate subducting) is where Approaching and Mastered separate. Reading the map is Approaching; explaining why the geology behaves that way is Mastered.
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 | Earth's internal structure | NY / Appr / Mast | |
| 2 | Plate boundaries & motion | NY / Appr / Mast | |
| 3 | Evidence for plate tectonics | NY / Appr / Mast | |
| 4 | Earthquakes & volcanoes | NY / Appr / Mast | |
| 5 | Lab technique (triangulation / maps) | 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.