RS4K Book 1 — Astronomy (Ch 18-21): K-2 stars/planets chapters. Foundation 100%, Gap 0.0%, Map Error 0.0%, Practices 92.9%, 1 cleared FSE (Sun size rounding). Nuclear fusion taught with proton/neutron rearrangement at K-2. Recommended Deep.
| Program | RS4K - Science Book 1 — Astronomy |
| Publisher | Gravitas Publications Inc. |
| Author | Rebecca Woodbury, Ph.D., M.Ed. |
| Grade Band | Grades 1-3 |
Verdict: ✓ Recommended — Deep. Foundation_calc 100.0%, deep tier. Practices 92.9% green (book-wide score). Zero map errors. 0 confirmed FSEs, 1 cleared.
Strict atomic-foundation scoring. The Astronomy quarter of Book 1 (Chapters 18-21) uses the atoms-and-molecules framework established in the Chemistry quarter as the explanatory anchor. Adjusted Gap 0.0%, Map Error 0.0%.
Chapters 18-21 extend the atoms-and-molecules framework into the cosmos. Ch 18 introduces astronomy and the Copernicus/Galileo episode as an example of argument from evidence. Ch 19 covers Earth, Moon, Sun system. Ch 20 explains the Sun as hydrogen atoms fusing into helium atoms with proton/neutron rearrangement — explicitly contrasted with chemical reactions that only involve electrons. Ch 21 frames terrestrial planets as made of rock and minerals, Jovian planets as made of hydrogen and helium gas.
"When hydrogen atoms stick together to make helium atoms, they rearrange their protons and neutrons. This is called a nuclear reaction." (Ch 20, p. 170)
"Terrestrial planets are made of rock and minerals, like Earth. Jovian planets are made mostly of hydrogen gas and helium gas." (Ch 21)
"Scientists argue about conclusions all the time, and arguing is part of science." (Ch 21 Pluto framing)
"The Sun is much larger than Earth. The Sun is so large that a million Earths would fit inside!" (Ch 20, p. 168 (cleared FSE — actual ~1.3 million))
FSE_CONFIRMED: 0. All flagged passages cleared as acceptable K-2 simplifications.
Map errors: 0. No OAO error (REI-substance, REI-agent, LAE, AEC all zero).
Practices: 92.9% green. Six of seven NGSS scientific practices PRESENT; mathematics is PARTIAL. Every chapter operationalizes the full arc (question → hypothesis → experiment → data → conclusion → share). The practices score is computed book-wide and applies identically to all five subject entries.
One passage could be tightened in a future edition without changing the verdict: Sun size could read ‘over a million Earths would fit inside’ to preserve magnitude without implying exactness.
The five RS4K Book 1 subject entries (Chemistry, Biology, Physics, Geology, Astronomy) all share Foundation 100%, Adjusted Gap 0.0%, Map Error 0.0%, Practices 92.9% — the curriculum’s architecture is uniform across subjects because Chemistry establishes the atoms-and-molecules framework that every other subject uses.
| Total Passages Scored | 18 |
| Raw Gap Error | 0.0% (6 mechanism passages — all anchored at atoms-and-molecules level) FALSE = atoms/molecules not present before students are asked to explain. The student is navigating without a starting point. |
| Adjusted Gap Error | 0.0% (0 UNSCAFFOLDED — atomic foundation established in Chemistry quarter, used throughout) UNSCAFFOLDED = no atomic grounding at all. LESSON_ATOMS = atoms mentioned elsewhere in lesson but not connected to this concept. |
| Substance-Model Errors (REI) | 0 Curriculum treats a process or outcome as a substance - "heat flows," "energy is stored," "electricity flows like water." Student builds a substance ontology. |
| Label-as-Explanation (LAE) | 0 Curriculum provides a name and treats it as an explanation - "this happens because of gravity." Student believes knowing the name IS understanding the concept. |
| Vague-Entity Errors (AEC) | 0 Curriculum uses vague entities ("tiny particles," "building blocks") without specifying atoms or molecules. Student invents their own model with macroscopic properties. |
| Factual Science Errors (FSE) | 0 Statements that are scientifically incorrect - not imprecise framing, but wrong. Any confirmed FSE = Not Recommended. |
| Practices | 92.9% - Deep Seven practices scored PRESENT, PARTIAL, or ABSENT and averaged: asking questions, developing and using models, planning and carrying out investigations, analyzing and interpreting data, using mathematics, constructing explanations and designing solutions, and argument from evidence. Higher is better, the opposite direction from gap and map errors. Reported but not part of the Foundation Score or the verdict. |
Sun’s hydrogen-to-helium fusion taught with proton/neutron rearrangement language at K-2. Planets framed by atomic/molecular composition. One FSE cleared as K-2 rounding.
Atomic foundation established in Chemistry (Ch 2-5) used throughout the Astronomy quarter. Sun’s hydrogen-to-helium fusion taught with proton/neutron rearrangement language at K-2. Planets framed by atomic/molecular composition. One FSE cleared as K-2 rounding. Practices 92.9% green (book-wide).
Recommended (Deep) — Deep by design -
Evidence for every entry is published at three levels. Each level states what it contains and what it leaves out.
Scores, verdict, and the full pattern count for this unit are above: adjusted gap, REI / LAE / AEC counts, FSE status, and the seven-practice score. Passage-level detail for this unit is carried in the downloadable evidence file.
This file covers the unit scored on this page.
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