Other
West Contra Costa Usd: Volume: A Foundation in Unit Cubes [Pdf]
A very detailed lesson on determining the volume of rectangular prisms, teaching students how to derive the formula for volume, and to use it successfully. Plenty of examples, student work, and assessment options.
Illustrative Mathematics
Illustrative Mathematics: 5.md Cari's Aquarium
This task supports the standard 5.MD.5.b in that it asks students to use the volume formula and conceptual understanding to solve real-world problems.