Volume and surface area
Volume is base area times height, and that stays true with fractional edges: a 2½ × 1⅓ × 3 prism has volume 10. A net is the surface unfolded, so surface area is the sum of the face areas on the net. Students match nets to cubes, rectangular and triangular prisms, and square pyramids, and compute surface area from a net or from dimensions. Surface area of a non-cube box is not 6ℓw; it is 2(ℓw + ℓh + wh). A net whose faces would overlap when folded is not a valid net.
Specification · for a parent or teacher
- volume-surface-nets
- Advanced Math 6 · Unit 12
- High School Math 1
- Shapes
- 3 of 4 — Grade 6–7 core. Multi-step, first symbolic work.
- 5 items
Students can
with fractional edges; match nets to cubes, rectangular and triangular prisms, square pyramids; compute surface area from a net.
Ready when
of a prism, and surface area of a given net, both correct.
Formulas
Watch for
surface area as for a non-cube; a net that folds into overlapping faces accepted as valid.