Great resource to conceptually explain volume to 5th graders. This lesson focuses on 5 main areas: 1. What is volume? 2. Counting Cubes 3. Finding Area and Number of Layers 4. Volume Formula 5. Application of Skills. This lesson explains volume in a systematic way that is outlined step-by-step. I suggest integrating exploration with this lesson where students find volume by filling small boxes with different sized cubes.