SWBAT discover the formula for the volume of a prism through problem solving

Students progress through a quick concrete->pictorial->abstract sequence of activities to understand area.

10 minutes

10 minutes

I will collect the unifix cubes before this section. Now we are moving to the pictorial activity. Students will be given a few minutes to answer the questions on the page. As students are working, I will walk around to assess student work. Problems 1 & 2 are essential for students understanding the generic formula for the volume of prisms, so I will initially focus my attention there.

Question 4 is an opportunity for students to develop a viable argument (**MP3**). The bullet points are provided to help them construct their arguments. Any number of answers may be appropriate, but they must be well constructed answers. For example: “I see that the number of cubes in each layer is equal to the product of the length and width of the prism.” A well formed argument will use language precisely as well (**MP6**)! Question C1 and C2 are so that students can see that rotations do not affect volume or surface area. We will have a share out of findings before moving on to the next section.

10 minutes

Now I would like my students to work through some problems independently. There are only 5 problems, so I expect everybody to make it to the extension questions. Notice these are just a variation on the warmup acitivity. The only difference here is that I only want unique combinations (not permutations). I will most likely not allow any calculator use as the problems are pretty straight forward and questions 4-5 provide a good review of decimal multiplication and division.

Extension question B is a review of surface area. It also allows students to develop **MP1** and **MP3**.

5 minutes

The exit ticket has 2 simple application problems and a slightly more difficult 3 problem, where the volume is given but one dimension is missing. It is very important that students show their work or explain their solution for problem #3. Some may write an equation; others may use arithmetic only. Either way is fine as long as they can justify the answer.