Preview · the opening missionRead this to the class:
In a classroom in Manila, a poster shows the eight planets in a neat row, almost touching the Sun, with the same small gap between each one. A student named Marisol asks: "Is Neptune as far from Uranus as Mars is from Earth?" Her teacher says the poster cannot tell her, because it is not drawn to scale. Your team's job: build the solar system to one scale with your own feet, and find out what the poster gets wrong.
Teams of three, with three jobs that rotate: Pacer (walks and counts out loud), Calculator (works out the paces), Recorder (writes and keeps the card).
Look inside the PDF
Sample pages, stamped “preview”. The download is the clean, full lesson.
In the full lesson PDF
9 printable pages
- Predict (5–10 min)
- Hunt (20 min)
- Reveal (10–15 min)
- Act (10 min)
- Background for the teacher
- Assessment
- Student sheet
- Worksheet: Planet distance cards
- Worksheet: Label it
- Worksheet: Try it at home
On the student sheet
- My prediction
- Our solar system in paces
- How big at the same scale?
- A better poster caption
- Exit ticket
- Planet distance cards
- Label it
- Try it at home
US Letter, prints cleanly in black and white. The student sheet is on its own page, ready to photocopy.
Free with an account (any 3 lessons), or US$19 for all 3 lessons in this unit.
What students show by the end
- Uses a scale
- Describes the pattern
- Explains the poster problem
From the lesson’s rubric, which scores each one as not yet, getting there or got it.
Questions teachers ask
How long does “How big is the solar system, really?” take?
50–60 min. Group size: teams of 3 (8 teams, one planet each; in a small class, teams take two).
How much prep does it need?
10 minutes: print the Student sheet for everyone and one set of Planet distance cards per team, cut apart. Find a straight stretch of schoolyard, field or corridor about 70 m (230 ft) long, or use the short version in the Teacher note.
What materials do I need?
None. No materials needed: just the printed sheets.
Which curriculum standards does it cover?
NGSS (US): MS-ESS1-3. It also matches England National Curriculum, Year 5 and Cambridge Primary and Lower Secondary Science (not endorsed by Cambridge).
What’s in the lesson PDF?
A teacher guide that walks you through predict, hunt, reveal, act, background for the teacher and assessment, then a student sheet (“My prediction”, “Our solar system in paces”, “How big at the same scale?”, “A better poster caption”, “Exit ticket”, “Planet distance cards”, “Label it” and “Try it at home”) on its own page, ready to photocopy. It’s US Letter and prints cleanly in black and white.
Can I try it for free?
Yes. A free account includes any 3 full lessons of your choice, and this can be one of them. After that, this unit is US$19 for all 3 lessons, yours to keep, or every lesson is US$199 a year.