Science Lesson Kit · Teacher Resource
Solar System: Planet Distances & Model Limits — 5E Lesson Plan
Space Science · 55 minutes
Grade 6
5E lesson flow
01
Engage
6 min
Teacher Does
Show a crowded planet poster and ask what it may hide.
Students Do
Point out possibly misleading equal spacing.
Ask
- Does this drawing use one scale?
Look For
Students question the diagram, not just name planets.
02
Explore
17 min
Teacher Does
Introduce AU data and model scale; demonstrate Earth at 1 cm.
Students Do
Mark Mars, Jupiter and Neptune on a strip.
Ask
- How will we check the model with data?
Look For
Students use the consistent 1 AU = 1 cm scale.
03
Explain
9 min
Teacher Does
Discuss why a radius strip cannot show simultaneous locations, planet sizes or actual scale of space in a poster.
Students Do
Write a claim supported by AU data.
Ask
- Do those marks show planet sizes?
Look For
Students distinguish model purpose from its limits.
04
Elaborate
15 min
Teacher Does
Introduce a new scale: 1 AU = 2 cm, without reusing online prompts.
Students Do
Solve a corridor-map planet placement problem.
Ask
- How does changing the scale affect every mark?
Look For
Students double positions consistently.
05
Evaluate
8 min
Teacher Does
Distribute the independent probe-planning worksheet.
Students Do
Use data, draw and explain two limitations.
Ask
- What can your model NOT tell you?
Look For
Evidence-based model critique.
Student goal
I can use average-distance data to make and check a scale model while explaining what my model leaves out.
Learning objectives
- Compare average Sun–planet orbital distances using Earth = 1 AU and evidence from a data table.
- Construct or audit a distance-only strip model, keeping its numerical scale consistent.
- Explain at least two model limits: planets do not stay in one straight line, and their sizes cannot be inferred from this distance strip.
Materials
- Thirty-five-centimeter paper strips or long chart paper
- Rulers marked in centimeters
- Colored pencils
- Printed rounded AU data card
- Student worksheet and answer key
Before class
- Print the rounded AU table and blank paper strip.
- Check enough paper length for Neptune at about 30 cm when the model uses 1 AU = 1 cm.
- Explain that models are about distance, not planet diameter or the positions of planets at one moment.
- No viewing the Sun directly with eyes or optical devices.
Prior knowledge
- Planets move around the Sun in orbits.
- Simple multiplication and decimals.
- Distances from Earth and from the Sun are not the same measurement.
Vocabulary
- solar system
- The Sun and the planets, moons, and other objects gravitationally bound to it.
- orbit
- The curved path an object follows around another object.
- astronomical unit (AU)
- A distance unit approximately equal to Earth's average distance from the Sun.
- scale model
- A model in which represented measurements are reduced or enlarged by a consistent rule.
- orbital distance
- Here, a planet's average distance from the Sun, not the changing distance from Earth.
- model limitation
- A detail a model simplifies, leaves out, or cannot show accurately.
Differentiation
- Give students a ruler and a table with rounded AU distances.
- Use a larger chart paper with 1 AU = 2 cm for learners needing more space.
- Provide frame: 'The diagram cannot show __ because __.'
- Advanced: compare a 1 cm-per-AU model with a hypothetical scale for diameters, explaining why both scales cannot be shown conveniently together.
Assessment
- Check Jupiter 5.2 cm, Earth 1 cm and Neptune 30.1 cm on the same strip.
- Listen for distinction between Sun distance and Earth distance.
- Review worksheet scale 1 AU = 2 cm with two explicit limitations.
Exit ticket
What does a solar-system distance strip show well, and what does it leave out?
Extension
Choose a longer hallway scale and explain how you know your printed strip is consistent.