Boat in a River – Airplane version

Take a moment … What do you notice? What do you wonder?

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Click to enlarge.

What could we do with this? Where could we go?

I saw this video today

It’s this video that made me think of creating the problem stated above. Did you notice in the original picture that the distances were the same? But the travel times were different? What was the speed of the plane? What was the speed of the wind?

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Click to enlarge.

I then thought of these problems…

A super common problem we see in our Grade 10 Academic course here in Ontario. The first airplane problem and this motor boat problem have no real difference but opening up the problem by asking “What do you notice? What do you wonder?” allows us as a class to narrow down to the problem together. It allows us as a class to discuss why the flight times are different. The class feels like they had a hand in coming up with the math for the day.

See also Dan Meyer’s Boat in a River problem — it’s a beauty.

Match My Graph & Crowd Sourcing Challenges

Here’s a quick synapsis of an activity from my Advanced Functions class with transformations of trig functions.

We used a Custom Polygraph from Desmos to generate talk/discussion on key properties of trig functions (Students have previously dealt with trig functions in grade 11).

I overheard students asking questions about x-intercepts, period, and amplitude. Awesome!

We took a note on key properties of the sine function and cosine function (We ran out of time for Tangent). 

Let the struggle begin!

Students were then asked to work through this Match My Trig Function Activity built using Desmos’ Activity Builder.

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Each slide is set up as a challenge. They are to write a sinusoidal function that “overlaps” the black target function. Students will have to use their memory or trial and error to discover how the parameters change the graph.

Watching the dashboard I can ensure their struggle is productive. I can jump in with feedback when I see they need it.

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Here’s the best part, once they completed all 12 challenges they created their own trig function matching challenge and shared it out on a Padlet board. We had crowd sourced a bank of challenges to work through!  The students didn’t hold back either… They wanted to create hard ones to push their friends.

See the challenge – Live Board Below

Can’t see this board? Click here

That’s where class ended. When we came in the next day  and they all choose at least 5 peer challenges to complete…. And that’s when the taunting began!

To end it off we took a note based on their discoveries of how the parameters changed the graphs.

Click here to create your own Custom Activity Builder or here to create your own Padlet board.



Promote Struggle – A Hero’s Journey in Math Class

While in Miami for the Apple Distinguished Educators Institute we saw a speaker from Pixar (I can’t recall his name) discuss the aspects of Story. More specifically he spoke about the Hero’s Journey. That talk really hit home for me. Below is how I interpreted his message and how it relates to my classroom.

A Hero’s Journey

All of these characters take a hero’s journey….

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Since I’m a math teacher describing the Hero’s Journey is best done with……a graph (English teachers will know it’s shown as a cycle).

On a time vs. Tension graph the Hero’s Journey looks like this: Time is the length of the journey….or story. The tension is felt by the audience. 

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In the beginning the hero is introduced, the main conflict is introduced, his/her world starts to change. As the story continues the hero must battle the forces of evil & go through struggle. They must experience conflict. It’s the conflict that the hero learns about themselves. They learn their strengths and weaknesses. It’s the struggle that makes the ending awesome. Its the struggle that make the hero see the solution. It’s the lessons they’ve learned in the struggle that let’s them go aha! I know what I need to do! The story would mean nothing to the hero and the audience if the climax was much earlier in the timeline. As the story ends the character returns to a NEW normal. They take their learning and come out stronger on the other side. 

This curve we see above is nothing new to us. This curve is what learners go through. It’s a Learner’s Journey too.

Now, if we take a look at our traditional math classrooms we have a format much like this:

Photo credit: Kyle Pearce

Photo credit: Kyle Pearce

Let’s look at that structure on the Time Tension graph. 

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After we take up homework, we introduce the new lesson or topic or problem to work on. It’s unfamiliar so tension in our students starts to increase.  But what happens is that as the tension rises it immediately falls back down. And my good buddy Kyle Pearce mentioned to me that the tension doesn’t fall all the way back to the axis….a good number of our students feel that tension permanently. 

Why does the tension fall immediately?

We make that happen. We relieve students of their pain by immediately telling them HOW to solve the problem.

Screen Shot 2015-11-17 at 9.59.24 PMIt’s Our examples & solutions. Students don’t get a chance to struggle & discover, Therefore the math formula, strategy or algorithm means nothing to them! The memorizers will memorize and do ok, and the non-memorizers lose again. The ideas and strategies have no real value to them. 

I think students should feel the need for the math they learn. They should experience struggle ….just like the hero.Screen Shot 2015-11-17 at 10.20.30 PM

Let’s take the old model of our lessons and change it to match the Hero’s Journey. It’s the struggle that adds value to their learning. Let’s move the reveal of math rules etc farther in the timeline. Let’s let the students productively struggle through problems. The reveal of the “math” will mean so much more after students see and/or feel the need for it. 

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An example in my class this week came when I wanted to teach students how to determine an equation of a quadratic function when given some key points.

I gave them this simple Desmos Activity Builder slide.

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Students already knew about vertex form of a quadratic function so I knew they could put in most of this equation. It’s the “a” value that they really didn’t know how to get efficiently. So I saw a lot of this…

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Students used trial and error to find -1/4 as the right “a” value. But we then asked “How do we know that’s the right one?” We then discussed plugging in a point to check to see if the right side equals the left side. They had a few more slides just like this but with different points. By the end of the last slide you could see that they really wanted a more efficient way of determining the “a” value than guessing and checking. This is where I stepped in and we discussed the idea of using one of the points and the equation to solve for the “a” value. Everyone was on board! They all had struggled before we discovered an efficient strategy. They all wanted it. If I had started class by showing them the first slide and then just telling them how to do it, I would see lack of understanding of why and bored faces.

It’s the struggle that makes the math worth it! Let’s let our students be Heroes. How are you promoting struggle in your classroom? I would love to hear of your ways. Leave a comment below.

Click here to grab the Desmos Activity Builder Activity I showed above.

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Angular Velocity, Trig Whips & Elmo

The #MTBOS is an amazing group of dedicated generous teachers!! This lesson came together because teachers are happily sharing what they are doing!

Generating Curiosity!

Dan Meyer has a series of blog post on Developing the Question you need to read. In one example he uses this video below to spark student wonder and start a fight. I copied his plan on how to use the video to generate discussion on speed.
Show this video

Pause the video before the bike is revealed and have students wonder “What is going on here?, What could the dots be?” Let the video play and then ask them to rank the dots from fastest to slowest. This is where wonder will happen. Are dots B and C moving at the same speed? What do we mean by speed anyway? Enter angular velocity vs. linear velocity.
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An Example for Linear Velocity vs. Angular Velocity

Show them this video obviously fake but fun video to generate some discussion.

Main Question we looked at together:How fast is the top swimmer moving when he hits the water? How fast is his angle changing? Before we calculate any of these we’ll go and experience the difference between the two.

Experience the Change

Bob Lochel has a great activity called Trig Whips where in groups of 4 students will experience the difference between angular velocity and linear velocity. Read about it!
A few pics and videos of our class Trig Whipping!

Whole Class


We came back in and summarized our findings from Bob’s handout. We made it clear that everyone had the same angular velocity but we all had different linear velocities. We turned our attention back to the diver video and determined the angular velocity and linear velocity of the top diver.



That’s where class ended! Tomorrow we’ll start off with….

Andrew Stadel’s Elmo Problem!

See all the resources from Andrew here
Tomorrow we’ll find Elmo’s ending position after the 1 minute, angular velocity and linear velocity.