Unit Plan 4 (Grade 2 Science): Solids, Liquids & Shape

Focus: Investigate how solids keep their own shape while liquids take the shape of their container, and explore water as a material found on Earth in solid and liquid forms.

Grade Level: 2

Subject Area: Science (Physical Science • Earth Science • Science & Engineering Practices)

Total Unit Duration: 5 sessions (one week), 30–45 minutes per session

I. Introduction

In this unit, students explore the big idea that materials behave differently depending on whether they are solids or liquids. They handle and observe classroom solids (blocks, crayons, toys) and compare them with safe liquids (water, colored water or oil in closed containers), noticing that solids keep their shape and liquids flow and take the shape of their container. Students then focus on water as a special material found in many places on Earth and in different states (solid ice, liquid water), obtaining information from pictures, books, and simple maps. Throughout the week, they plan and conduct basic classification investigations (2-PS1-1 support) and gather information about where water is found and how it can be solid or liquid (2-ESS2-3).

Essential Questions

• How can we tell the difference between a solid and a liquid by how it keeps or changes shape?
• Why do solids keep their own shape while liquids take the shape of the container they are in?
• Where do we find water on Earth, and in which places is it usually solid or liquid?
• How can observations and simple tests help us describe and classify materials as solids or liquids?

II. Objectives and Standards

Learning Objectives — Students will be able to:

1. Describe solids as materials that keep their own shape and size when moved from place to place.
2. Describe liquids as materials that flow and take the shape of their container while keeping about the same amount (volume).
3. Plan and conduct simple investigations to observe and classify materials as solids or liquids based on observable properties (2-PS1-1 support).
4. Record observations in simple charts or drawings showing how solids and liquids behave in different containers.
5. Obtain information from pictures, books, or simple maps about where water is found on Earth (oceans, lakes, rivers, glaciers, snow) and whether it is solid or liquid (2-ESS2-3).
6. Explain with simple language that water can be a solid (ice/snow) or liquid (water) and connect examples to places on Earth.

Standards Alignment — 2nd Grade (NGSS-Aligned)

• 2-PS1-1 (support) — Plan and conduct an investigation to describe and classify different kinds of materials by their observable properties (here: solids vs. liquids).
• 2-ESS2-3 — Obtain information to identify where water is found on Earth and that it can be solid or liquid.

Success Criteria — Student Language

• I can tell if something is a solid or a liquid by how it keeps or changes shape.
• I can plan and do a simple test to see how solids and liquids behave in different containers.
• I can record my observations in a chart or drawing that shows if a material is a solid or a liquid.
• I can name at least two places where water is found on Earth and tell if it is usually solid or liquid there.
• I can explain that water can be ice (solid) or liquid water, and give an example of each.