Topic 21 Earth, Moon and Sun, and our place among the stars — what needs James (34)
28 question types · 6 lessons. Tap a button on each card; the ruling goes to the build and the card shows it as ruled.
Question types
Question types (28 to rule on) →
The lessons (6)
Each lesson in teaching order: its one-line summary, the article, the script and the quiz, then your ruling.
Topic 21 · Lesson 1 · Video / article words: 149 / 400 · Quiz items: 10 · Figures: 8
Lesson 1 The parts a model of a system needs
The lamp stands for the Sun, the globe for Earth, the marble for the Moon; the lamp off, the marble away, a bigger ball, a toy rocket; take a part away and see if the model still does its job; "system" coined
Topic 21 · Lesson 2 · Video / article words: 150 / 393 · Quiz items: 9 · Figures: 6
Lesson 2 Show how Earth, the Moon and the Sun move, all at once
One turn of the globe is one day; one trip of the marble is about a month; one trip around the lamp is one year; all three at once, each at its own pace; spinning is not traveling around; the Moon's path is the same every month
Topic 21 · Lesson 3 · Video / article words: 141 / 258 · Quiz items: 8 · Figures: 3
Lesson 3 Farther away looks dimmer
The same flashlight from beside the bench, halfway, the far end and back; a street lamp at one, two and six times the distance; two of the same lights, the dimmer one is farther; only for lights of the same kind
Topic 21 · Lesson 4 · Video / article words: 150 / 297 · Quiz items: 8 · Figures: 6
Lesson 4 Why the Sun outshines the stars
The Sun is a star; the same light looks dimmer farther away; the Sun is far nearer than any other star; so it looks far brighter, and for no other reason; by day the stars are still there
Topic 21 · Lesson 5 · Video / article words: 147 / 217 · Quiz items: 8 · Figures: 5
Lesson 5 What a galaxy is
The swirl breaks into separate dots, each a star, more than anyone could count, gas and dust between; an oval galaxy too; a star pattern is a few stars, a galaxy countless; "galaxy" coined
Topic 21 · Lesson 6 · Video / article words: 149 / 239 · Quiz items: 9 · Figures: 4
Lesson 6 Our galaxy: the Milky Way
The Sun is one star in a galaxy, the Milky Way; Earth is inside it; a flat disc of stars, and looking along it the light of countless stars runs together into a band; every star seen one by one is inside it; "the Milky Way" coined
Skill: write-like-james @ 2d96464 · built 8 October 2026 by build_tools_needs_you.py