Unit Plan 6 (Grade 6 Science): Scale of the Solar System
Grade 6 unit using data, graphs, and scale models to compare planet sizes and distances, building accurate understanding of solar system scale and spacing.
Focus: Analyze and interpret data on the sizes and distances of solar system objects to build a sense of scale, using models, graphs, and ratios to compare planets, moons, and the Sun.
Grade Level: 6
Subject Area: Science (Earth & Space Science — Space Systems • Data & Scale Modeling)
Total Unit Duration: 5 sessions (one week), 50–60 minutes per session
I. Introduction
In this unit, students confront how huge and spread out the solar system really is. They analyze data tables for diameter, distance from the Sun, and orbital period to compare relative sizes and spacing of planets and other objects. Using scaled models, simple ratios, and visual representations, they discover that even when planets are drawn to scale, the distances between them are vastly larger than their sizes. Students build a more accurate mental model of MS-ESS1-3 by working with real-world data rather than guessing from not-to-scale diagrams.
Essential Questions
- How big are the Sun, planets, and moons compared to each other in size?
- How far apart are objects in the solar system, and why is it hard to draw both sizes and distances to scale at the same time?
- How can data tables, graphs, and scale models help us understand scale properties of the solar system?
- What are some strengths and limitations of common solar system diagrams in textbooks and posters?
II. Objectives and Standards
Learning Objectives — Students will be able to:
- Read and interpret data tables showing diameters and distances from the Sun for solar system objects.
- Use ratios and scale factors (e.g., 1 cm = X thousand km) to build or critique scale models of planet sizes and orbital distances.
- Construct or analyze graphs and visual representations (e.g., bar graphs, comparative strips) to compare relative sizes of the Sun, planets, and selected moons.
- Explain why most pictures of the solar system cannot show true scale for both size and distance at the same time, and identify what they do and do not show accurately.
- Describe how analyzing and interpreting data on size and distance supports MS-ESS1-3 understanding of scale properties in the solar system.
Standards Alignment — 6th Grade (NGSS-based custom)
- MS-ESS1-3 — Analyze and interpret data to determine scale properties of objects in the solar system.
- In this unit: students focus on relative diameters and distances from the Sun, using data to build and critique scale models and visual comparisons.
Success Criteria — Student Language
- I can read a data table and tell which planets are larger or smaller and closer or farther from the Sun.
- I can use a scale (for example, 1 cm = 10,000 km) to create or understand a scaled model of planet sizes or distances.
- I can explain at least one reason why it’s hard to draw the solar system at true scale.
- I can point to a diagram or graph and describe what it shows correctly about size or distance.
- I can describe one strength and one limitation of a solar system picture or model.