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Made by Matt · GROW Science · Week 6

Use a model, name its limits

Use a model and year data to explain planetary motion.

Tuesday · 09:30–10:10

Choose one task, model or clip within the current lesson stage. These resources support the existing two separate 40-minute lessons; they do not add another lesson or extra time.

Worksheet PDF

We Do · think together

Test a year-length claim

Approximate orbital periods in Earth days. Which comparisons support “farther out, longer year” for these planets?

A model helps explain an idea. It does not measure real planetary motion or prove an observation. Label any given numbers as reference values.

Approximate reference values, not class measurements
PlanetYear / Earth days
Mercury88
Earth365
Mars687
  1. Compare Earth with Mars.
  2. Why is a single hand-made orbit not enough evidence to measure a year?

Discuss, point, draw, write or dictate a first explanation. Choose one example first; extend only if there is time.

Reveal a worked explanation after an attempt

Mars takes about 322 more Earth days than Earth (687 − 365). Mercury’s 88 days is shorter than Earth’s year. The reference values support the stated pattern for these examples; hand speed in a counter model is chosen by us.

Give a smaller support cue

Use “The model shows … . It does not show …”. Compare 687 with 365.

Writing stays in this open page only. It is not saved or sent. Copy any record you want to keep before leaving.

Apply it

Use the current workshop

Draw a two-arrow orbit model and use two values from the table to explain a year-length comparison. Add one limitation of your model.

Teacher model · compare with the pupil’s evidence

Gravity points towards the Sun; motion is along the curved path. Mars’s year is about 687 Earth days, longer than Earth’s 365. A counter model does not show real scale or orbital speed, and our hand is moving it.