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KS3 Earth and atmosphere · 15 minutes · no login

Solar system

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Why this lesson, and why the 3D

Solar system is a fifteen-minute projector lesson, not a homework packet and not a film with a quiz bolted on. Put this hook on the board before you dim the lights: Eight planets, one star. Distances are the lie a classroom model always tells — we exaggerate so you can see them. By the end of the slot a pupil should be able to name the eight planets, compare orbital periods, and treat size as labelled exaggeration. Curriculum tags in the header (KS3 Earth and atmosphere; NGSS MS-ESS1-2; GCSE background) are filters, not a flag. The room is worldwide; SI first; International English. Ages on the card (KS3, NGSS MS) are a suggested band, not a gate.

A London planetarium kit parks Jupiter beside Mars on a table. A night sky over Miami does not. Distances are the first lie every classroom model tells, and this lab names it. Greenwich treats Earth as a labelled planet, not a special case. The same star that lights a Holderness beach lights Hawaii. Eight names. Two families: rock, then gas and ice. A ring you can point at from the back row. Scale literacy is the skill. If you cannot say which number is size and which is orbit, you cannot read a NASA poster, a GCSE diagram, or a news graphic that sits Saturn next to Earth. Fieldwork does not need the plastic kit. It needs one sentence: closer planets lap the outer ones; periods lengthen with distance; sizes on the table are not the same lie as the gaps. That sentence travels from Leeds to a Florida pier without changing.

The 3D is a named, inspectable object. Click the part, not a caption. If the model will not spin, the Why panel still carries the mechanism, the two photographs, and the film. Do not apologise for the model. Drive it. A silent spin teaches a screensaver. A named mesh that changes under a slider teaches the process.

Fifteen minutes on the projector

Play a year. Name the inner four, then the gas giants, then the ice giants. Saturn’s ring is ice and rock, size exaggerated. Say that before anyone calls it a solid disc. Toggle True distance. Planets become dust. That is the honest sentence. Toggle back to visible mode so the set reads from the back row. Periods lengthen with distance. Kepler, not astrology. Ask which planet laps Earth first. Mercury. Ask why Neptune is slow. Distance, not bulk. Pluto is not on this table. Do not apologise for that. Two scales cannot both be true in one plastic kit. Finish in Check.

Open the lab full screen (F). Labels on (L). Speak the first step before you touch a slider: Play a year. Inner planets lap the outer. Then the second: Pause on Saturn’s ring and Jupiter’s size. Then the third: Periods lengthen with distance. Sizes here are not to scale with orbits.

The sliders that earn their keep are True distance. Space plays; arrows nudge time; R resets. Parameters the URL can remember: trueScale. If you only have eight minutes, skip the last step and finish in Check. Projector layout (P) is for the back row: one idea, large type, the model still live.

Play a year. Space toggles play. Arrows nudge time. Speed is 1×, 2×, or 4× on the bar. Toggle True distance: classroom set versus compressed AU. L labels. R reset. P projector. No explode, no slice. Pause on Saturn’s ring. Pause on Mercury lapping Earth. Reset if the class has lost the inner four. The year slider is the orbit clock. Names are the point. The toggle is the honesty. Leave True distance off for the back row, then on once so they hear the dust sentence.

The in-site film is “How Does the Earth Move? Crash Course Geography #5” (Crash Course Geography, about 11 min, Crash Course / Complexly on YouTube. Standard YouTube licence. Educational embed, autoplay off.). Autoplay is off. Play one minute if you need a second voice; do not let the film eat the slot. The 3D still has to move under your hand.

What the third row will get wrong

You will hear the misconception before you have finished the first sentence. Write the false claim on the board and leave it there until the model has contradicted it. Do not skip this. A fluent pupil can recite the hook and still believe the false sentence.

“The model on the table is to scale.” — no. If orbits were to scale, planets would be dust.

“Pluto should be on this table as a planet.” — no. Eight planets. Pluto is a dwarf planet. This lab does not park it in the set.

“The outer planets take longer because they are bigger.” — no. Period follows distance, not girth. Kepler: closer, faster. Neptune is slow because it is far.

Pitfalls to keep in your pocket: Astrology dressed as orbital period. Treating size and orbit as one scale. Parking Pluto as a ninth planet in this set. Calling Saturn’s ring a solid disc. Do not let a pupil leave thinking the 3D is a photograph. It is a teaching model. Where vertical exaggeration exists, T collapses it and the caption says so. A labelled lie of scale is honest. An unlabelled one is a cartoon.

Two places, not a slogan

Input is time: one school year on the slider. The Sun sits still. Eight planets run their rings. Mercury, Venus, Earth, Mars lap the outer four. Jupiter, Saturn, Uranus, Neptune take longer because they are farther, not because this lab plots mass as the clock. What moves: position on the orbit. What does not: the order of the eight, the Sun’s place at the centre of this set, the fact of closed paths. What is conserved: Kepler’s bargain — closer, faster. Period squared with distance cubed, in school language. Toggle True distance and the set tells a different honesty. Orbits stretch toward astronomical units. Planets shrink toward dust. You cannot keep both size and orbit honest on one table. That is the lie visible mode tells on purpose, so the back row can still name Saturn’s ring. The ring is ice and rock, drawn fat. The Sun is a ball you can see, not a 109-Earth-diameter monster at a true gap. Periods stay true-ish: Mercury about 88 days, Earth a year, Neptune about 165 years. Astrology is not in the room. Size is not orbit scale. If the orbits were true and the planets were true, you would need a field, not a screen.

The first place to land is Earth as a labelled planet. The second is Insolation starts at the Sun. Same process, different rock or climate. If a pupil can only name one place, they have a postcard, not a mechanism. Atlas entries for those names are a click from the case list; send them back to the lab with one sentence they can say in Check.

Do not flatten the comparison into “this country versus that country.” Name the landform. Holderness is till, not chalk. Hawaii is a hotspot, not an island arc. Yosemite is a glacial trough, not a river canyon. The 3D is allowed to be schematic; the place names are not allowed to be sloppy.

Figures and the film

Field photograph: The Sun and planets as a family of spheres. A sphere among other spheres. Credit: NASA, public domain.

Mechanism photograph: Field or official figure for teaching Solar system. A second photograph for the projector script — not the lab cover. Credit: Wikimedia Commons / NASA / USGS.

Two photographs, two jobs. The field picture is the place. The mechanism picture is the process. Do not run the lesson on a single Apollo Earth disc. A carbon-cycle class is a forest and a seam, not a blue marble. An ENSO class is a Pacific temperature map, not Africa from Apollo 17.

Words they must be able to say

Say these out loud once while you click the matching mesh. If a word has no mesh, it still has a photograph in Terms.

Orbital period: Time for one trip around the Sun. Mercury ~88 days. Earth 1 year. Neptune ~165 years. Terrestrial planet: Mercury, Venus, Earth, Mars: rock and metal, close in. Exam language also accepts “Rocky planet”. Gas giant: Jupiter and Saturn: thick hydrogen–helium envelopes. Not small rocky worlds with weather like ours. Ice giant: Uranus and Neptune: ices of water, ammonia, methane over a denser interior. Farther and slower than the gas giants. Astronomical unit: Earth–Sun distance, about 150 million km. The school unit for the inner system. Exam language also accepts “AU”. Kepler’s third law: Closer orbits are faster. Period squared scales with distance cubed. This lab shows the qualitative half. True scale: A mode where distances lean toward AU and planets shrink toward dust. Still compressed. Still a lie, just a different one. Planetary ring: Ice and rock in orbit, here Saturn’s. Drawn fat so the back row can see it. Not a solid disc.

Exam-language toggle (the Teacher tab) swaps UK/US pairs where they exist — levée/levee, arête/arete — so a mixed room is not punished for spelling.

Close the slot

If the model will not spin, keep the sentences. Eight planets, one star. Inner four are rock. Outer four are gas and ice giants. Closer orbits are faster. Sizes in a kit are exaggerated so you can see them. True orbits would leave planets as dust. Saturn has a ring of ice and rock. Neptune takes far longer than Earth. Pluto is not on this table. That is enough to sit Check without WebGL, and enough to catch a poster that pretends two scales at once.

Finish in Check — ten questions, not a mood. The bank mixes definition, process, the misconception you just killed, a named place, and a read-the-model item (click the part; T). If a pupil can only recite the hook, they have not used the geometry. Wrong answers still show the one-line explain. Do not skip the explain.

Sources on the Teacher tab are the trail, not a bibliography to copy. NASA solar system.

Link back to the live lab and keep the same slug. Do not invent a parallel worksheet that contradicts T, SI, or the named parts.

This note is worldwide. Curriculum tags (KS3 Earth and atmosphere; NGSS MS-ESS1-2; GCSE background) are filters, not a flag. A class in Nairobi, London, or Shanghai can use the same 3D. Ages (KS3, NGSS MS) are a suggested band. If a sentence only works in one exam board, rewrite it before you project it.

Write these three lines on the board before you dim the lights. One: Eight planets, one star. Distances are the lie a classroom model always tells — we exaggerate so you can see them. Two: the misconception “The model on the table is to scale.”. Three: the named parts they must click. Then drive the model. Check is ten questions covering definition, process, the misconception, a place, and a read-the-model item. Do not skip the explain on a wrong answer.

Board, units, and what not to say

SI first. Metres, kilometres, degrees Celsius, metres per second. A conversion in brackets is courtesy, not a second system. Do not let a pupil leave thinking the 3D is a photograph. It is a teaching model. Where vertical exaggeration exists, T collapses it and the caption says so.

Do not say “teaching mesh”, “sprinkle”, or “thin free surface not a fat pipe” out loud. Say the landform. Seasons are ~23.44° of axial tilt, not Earth–Sun distance. The outer core is liquid; S-waves do not pass. Yosemite is a glacial U-trough. San Andreas is a transform. Hawaiʻi and Yellowstone are hotspots. Florida is not a glacial trough.

If the room is noisy, projector layout (P) is the back-row setting: one idea, large type, the model still live. Full screen (F). Labels (L). Space plays. Arrows nudge time. R resets. The URL can remember trueScale. Send them home with the same link; there is no login.

In-site film

How Does the Earth Move? Crash Course Geography #5. Crash Course Geography. Crash Course / Complexly on YouTube. Standard YouTube licence. Educational embed, autoplay off. Autoplay off.