Volume of rectangular prism

Watch the following video paying attention to the way in which the teacher uses layers to calculate the number of cubes used in the prism. Record in your book how many cubes are in each layer and how many layers there are. Can you write a mathematical sentence using this information to show how to calculate the number of cubes in the prism?

Using Layers to find Volume of Rectangular Prisms

Now we are going to extend this a bit further. Have a play with this application to change the volume of the rectangular prism by changing the height. Using what you know about layers, can you write an explanation of what is happening in your book?