Angle of Elevation - Activity

on Wednesday, April 26, 2017
Today we did a great activity that allowed students to get excited about SohCahToa and angles of elevation.

The Set up:
Last week we did an AMAZING 3 act using SohCahToa. Check out the videos here. This helped them remember what they did in Geometry with trig. Then yesterday I re-introduced my students to SohCahToa in a more formal way. We went through how to solve for angles and sides.

The Plan:
Today I started by having them pull out their iPhone, if they had one. (In my school I can count on at least half of the students having an iPhone). I asked students to open the Compass app and swipe right. When they do this, the level opens up. Students with androids were able to look in their app store and find many free levels that did the same thing.

I gave students the instruction: "Figure out how this works." A few minutes later I asked them to hold it in landscape view, parallel to a wall. Then I asked them to, by tilting left and right, figure out what the negative numbers are.

After a little exploration, I instructed students to pick up a half straw that was on their desk -- I told them to place it on top of their phone and use it like a scope. We then practiced looking at random things in the classroom and having a partner read them the angle they were looking up at.

Then, I drew a picture of a flagpole on the board and said "There is a flagpole outside our school. We're going to figure out how tall it is. Now, we're not going to climb up it, and I don't have anything that can reach to the top of it. At your table, sketch this situation on your whiteboard and see if you can figure out how to determine how tall it is." I gave students a few minutes to talk and draw -- they were excited! In their groups realized they could get the angle, and they also realized they could probably get the distance along the ground.

I have a measuring wheel that I bought from Harbor Freight for probably about $15 a few years ago (think -- this is what cross country coaches use to measure their course). I showed them how to work it, and then we headed outside. Students took their measurements in groups of 3 - 4 to help save time in sharing the measuring wheel.



I created a google form for students to submit their group members names and their calculated measurement. I'll check it out later tonight to see who got the closest and give them a prize!


This was a super fun activity and I hope you try it out. If you would like an activity page to accompany it, check out this link.

I do this activity on a block day -- afterwards we practiced drawing pictures for different scenarios of angles of elevation and depression. Then I've used the worksheet below the past few years and enjoy it! The last few problems are good thinking ones!
Angles of Elevation worksheet
Answer key