This is the third year our family has set up an above ground pool in our backyard. It takes quite a bit of time and effort to get it set up but it’s worth it since our kids love water and truly are fish. First we have to level the ground so it is perfectly flat. Last year we took a shortcut on this step which turned out to be a very bad idea. Just as we finished filling the pool we observed a noticeable lean which would have led to a quick collapse. We drained the pool and started again 😦 The next step is to put up the pool frame, liner and filter system. Since this was our third (actually fourth) attempt we are getting much faster. Finally we fill up the pool with water, add the chemicals and we are ready for fun!

Over the past year I have watched amazing educators create videos that I’ve used with students to make math and learning through problem solving come alive. Dan Meyer, through his TED Talk, *Math Class Needs a Makeover*, was the first person I saw doing this. He has shared a ton through his blog where he features his WCYDWT (What Can You Do With This) section. He also introduced the #anyqs idea that has gone viral via Twitter. He, along with so many other talented educators, have inspired me to create a math video along with support materials. So here it goes…

This post is the culminating project for my first video. I set up my camera to take photos at regular intervals while we were setting up and filling the pool. I created a short video from these stills and then I had to make sure I had all the information students would need to answer their questions. I provided these details in photographs that teachers can use when students request specific measurements.

I think that students in grades 5 to 9 could do this activity. Students in the higher grades would be able to do more with volume and capacity whereas the younger students could use proportional reasoning.

My colleague, John Scammell, has identified seven steps of Learning Through Problem Solving approach. I’d like to use his framework to present how we can use this activity with students.

- Begin by showing this video.

- Ask students what questions they would like to explore. I think one of the most obvious questions they will ask is, “
*How long does it take to fill up the pool?*” or they might wonder how much water is needed to fill up the pool. - At this point encourage students to guess answers to their questions. After some discussion, get the class to agree on a reasonable range of values.
- Next students may ask for any information they need to answer their questions. Provide the following photographs as needed.

Or you could show this short video to convey how long it takes for the water to rise one unit in the pool:

- Now let the students run with the problem. I have included both metric and imperial measurements in some of the extra photos I took that you can download as well.
- Gather student responses and encourage students to share their strategies. Offer time to reflect on their solutions and time to refine or readjust their work.
- For the solution on how long it took us to fill this pool, simply play this video and students can calculate the time it took. Remember to discuss sources of error – why the students’ calculations didn’t exactly match the real-life answer. The answer about how much water would be needed to fill the pool is in one of the extra photos of the pool box.

- I would finish by asking students to summarize what they had learned about this problem – what concepts they learned, what they will remember, anything shocking or surprising, etc.

One of the ways you could figure out how long it takes to fill up this pool is to calculate its capacity and use the rate of water flowing into the pool from the hose. I didn’t do that for this activity. It is my hope that I have included enough information that students can still solve it with the photos I provided.

You can download these videos on my YouTube Channel – question, answer and water rising. You can also download the photos here.

I took many more photos that I thought teachers could use. I have photos of the ladder and its maximum load, the frame components, the filter system as well as the chemicals required to maintain the pool. You can download these extra photos here. You could use some of these pictures with younger learners or to explore the problems in different ways. Here are two samples:

I’d like to make more math videos over the next school year so I’d appreciate your suggestions and comments. Was this a worthwhile context? Did the video and photos convey the information we wanted?