Unit Plan 10 (Grade 6 Science): The Rock Cycle
Grade 6 unit modeling how Earth’s materials cycle through igneous, sedimentary, and metamorphic rocks, driven by internal heat, the Sun, and gravity over time.
Focus: Develop and use models to show how Earth’s materials cycle through rock types (igneous, sedimentary, metamorphic) and how energy from Earth’s interior and the Sun drives these processes over time.
Grade Level: 6
Subject Area: Science (Earth & Space Science — Earth’s Systems)
Total Unit Duration: 5 sessions (one week), 50–60 minutes per session
I. Introduction
In this unit, students become “rock system detectives” as they explore how rocks are constantly changing inside and on the surface of Earth. Through hands-on observations, diagrams, and modeling activities, students learn to distinguish igneous, sedimentary, and metamorphic rocks and to trace how weathering, erosion, deposition, burial, heat, pressure, melting, and cooling transform one rock type into another. Students build and revise a rock cycle model that highlights not just the pathways among rock types but also the energy sources (Sun-driven surface processes and internal heat from Earth and gravity) that power these changes.
Essential Questions
- How do igneous, sedimentary, and metamorphic rocks form, and how can one rock become another over time?
- What processes (like weathering, erosion, deposition, burial, melting, and cooling) drive the rock cycle?
- How do energy from Earth’s interior, gravity, and energy from the Sun power the cycling of Earth’s materials?
- Why is the rock cycle considered a system rather than a simple one-way path?
- How can models help us see both matter cycling and energy flow in Earth’s geologic processes?
II. Objectives and Standards
Learning Objectives — Students will be able to:
- Observe and classify rock samples into igneous, sedimentary, and metamorphic categories based on visible properties and formation clues.
- Describe key geologic processes—weathering, erosion, deposition, compaction/cementation, heat and pressure, melting, cooling/crystallization—and connect them to rock type changes.
- Develop and use a rock cycle model to show how Earth’s materials cycle among rock types through a variety of pathways (not just in a circle).
- Explain how energy flows from Earth’s interior (heat, uplift, plate motion) and the Sun and gravity (weathering, erosion, transport) drive the rock cycle.
- Create and explain a final rock cycle model (diagram, concept map, or 3D representation) that correctly labels processes, rock types, and energy sources.
Standards Alignment — 6th Grade (NGSS-based custom)
- MS-ESS2-1 — Develop a model to describe the cycling of Earth’s materials and the flow of energy that drives this process (rock cycle, internal heat, surface processes).
- In this unit: students build and refine a rock cycle model showing rock type transitions and energy drivers (interior heat, Sun, gravity).
Success Criteria — Student Language
- I can sort and describe rocks as igneous, sedimentary, or metamorphic, using evidence from what I see.
- I can name and describe rock cycle processes like weathering, erosion, deposition, melting, and cooling.
- I can use a rock cycle model to show more than one path from one rock type to another.
- I can explain how energy from Earth’s inside and energy from the Sun and gravity power the rock cycle.
- I can create a clear rock cycle diagram or model and explain it so someone else understands how Earth’s materials cycle and energy flows.