CCSS.Math.Content.7.G.A.1
The standard
Solve problems involving scale drawings of geometric figures, including computing actual lengths and areas from a scale drawing and reproducing a scale drawing at a different scale.
Common Core State Standards for Mathematics · Geometry
What this standard means
Students need to read a scale drawing, use the scale factor correctly, and find real lengths and areas. They also need to make a new drawing at a different scale without changing the shape. They should know that side lengths multiply by the scale factor, while areas multiply by the square of that factor.
Mastery looks like careful labeling, correct units, and proportional reasoning instead of guessing. Students often mix up drawing length and actual length, forget to square the scale factor for area, or use the scale backward. They also may redraw figures neatly but not preserve all side lengths in proportion.
Ways to teach it
- Give pairs a floor plan on grid paper and have them compute real room lengths, then redraw one room at twice the scale.
- Ask students to explain why doubling every side of a rectangle does not just double the area.
- Use an exit ticket with one scale drawing, asking for one actual length and one actual area with units.
- Bring in a map or furniture catalog diagram and have students check whether a table would fit in a classroom space.
Plan a lesson for CCSS.Math.Content.7.G.A.1
Generate a complete lesson plan aligned to this standard, with objectives, activities, and materials. Free, no account needed.
Related standards
- CCSS.Math.Content.7.G.B
Solve real-life and mathematical problems involving angle measure, area, surface area, and volume.
- CCSS.Math.Content.7.G.A
Draw, construct, and describe geometrical figures and describe the relationships between them.
- CCSS.Math.Content.3.MD.D.8
Solve real world and mathematical problems involving perimeters of polygons, including finding the perimeter given the side lengths, finding an unknown side len...
- CCSS.Math.Content.6.G.A
Solve real-world and mathematical problems involving area, surface area, and volume.