Each Teacher Guide includes:

• Lesson Plans
• Paperback copy of the storybook Yi Min's Great Wall
• Teacher Background Information
• Assessment Tools
• English Language Learner suggestions

---

This unit addresses the use of earth materials in the design and construction of technology. What properties make an earth material useful? Different materials have different properties, making them appropriate for different uses. Students investigate various earth materials (clay, sand, and soil) to be used in a mortar to build a stone wall. They then design a mortar mixture, taking advantage of the properties of these different materials, and plan, create, test, and improve their own walls.

• FOSS Connection: Pebbles, Sand, and Silt
• STC Connection: Soils, Rocks and Minerals
• GEMS Connection: Stories in Stone