Monday, July 21, 2014

Tools: Helpful & Unhelpful

Not sure I made the best teaching move today, but I had to try it. We explored Dan Meyer's "Will it hit the hoop?" task(s).

Act 1: Roll "Take 1"
  • Agree on the question, "Will he make the basketball shot?"
  • Ask students to make a series of guesses for a total of six takes.
Act 2: Ask for information
I typically ask students to think of information they would find useful in answering the question. Today, I went somewhere else with Mathematical Practice 5. I asked students to make two lists:
  • List 1: Math tools that would be UNhelpful.
  • List 2: Math tools that would be helpful.
This is the fourth and final week of the summer academy. My students have been exploring many math tools. I'll list the activity/task with the prevailing tool(s):
As you can see, many of our tasks were dominated by slope-intercept and Desmos. I didn't find their lists surprising.

I love how some students thought Desmos would be helpful, while others thought it'd be helpful. Those that found it unhelpful, wished you could insert images into Desmos so they could use sliders to find the path of Dan's shots. Boy, were they happy when they discovered you could import images. My first class was split down the middle: half thought slope-intercept might be useful and half didn't. It took a few convincing students to explain why Vroom Vroom was an example where a linear function was unhelpful.

Overall, I'm pleased with this approach, but I wouldn't do it with every task. It might confuse students that there's only one way to solve a task and detract from the importance of MP 5. I thought this was a fitting opportunity for students to mainly see the difference between a linear function and quadratic function. Specifically, I wanted them to see the advantages of using sliders in Desmos with a quadratic function instead of a linear function. I think students need to shuffle through their tool belt often and pick the right tools for the right task. I think today it was necessary. Dan has written about this or breaking students' tools. Moving forward, it's a matter of using this strategy at relevant times and not overusing it. However, I might be wrong altogether. That's where it's your turn to chime in...

Tomorrow: Des-Man!


Sunday, July 20, 2014

Estimation 180 Gear

They're here! Estimation 180 t-shirts and stickers! Yes, I'm excited.

Estimation 180 was born out of my love for number sense and visual mathematics. In addition, it was important I help my students develop better number sense and see the world of mathematics in a different way. Little did I know, the site would make its way into classrooms across the United States, Canada, and other parts of the world. Thank you all for tweeting or emailing your experiences as I find it so cool that students are exploring number sense in your classroom and having mathematical conversations, sometimes even constructive arguments.

It makes my math heart full of joy to see other teachers do amazing things with Estimation 180 and beyond. Please make some time to check out blogs like Joe Schwartz, Jonathan Claydon, Mary Bourassa, and Megan Schmidt who are just a FEW of the teachers taking the idea and running with it. Teachers like MichaelHedge, DanRobert, John, Matt, and others spread the Estimation 180 love when doing teacher trainings or presentations. I couldn't be more appreciative and grateful. Thank you! Chris Harris even shared some bacon estimations to a roomful of parents one weekend.  I love how the site has become an instrument to help teachers create a classroom of curiosity with students, building number sense along the way. In addition to daily estimation challenges, the site has many of the lessons I've developed over the past few years.

These shirts are just another extension of my passion for number sense. As I present at conferences and give teacher trainings, I'm excited to give away some t-shirts to attendees nailing estimation challenges built into my workshops. Likewise, stickers are available for you to stick some number sense in your favorite place. This is how I roll!

I'm not in this to make money. This is more of a hobby to go along with the site. I would be eternally grateful if you decide to buy shirts and stickers and spread the Estimation 180 love. Head over to the Estimation 180 store and check out the shirts, their sizes, and how easy it is to order.

Nuts and Bolts:
If you're interested, I think it'd be good to be transparent on the nuts and bolts behind the t-shirts and stickers. If you're not interested in the nuts and bolts behind the t-shirts, skip the rest of this post and check out the t-shirts and stickers.

No outside party is financially backing Estimation 180. AND I don't plan on charging for using the site, ever! Therefore, I have done everything I can think of to make these shirts as affordable as possible, because I'm not in this to make money. Any money made from shirts and stickers would go back toward web costs associated with Estimation 180 and the free t-shirts and stickers I would pass out at conferences. As you can imagine, it's been one huge math task keeping track of expenses in order to set reasonable price points for the t-shirts and stickers so that teachers can afford them.

$20 for a shirt gets you a lot! You get a high-quality shirt for one. This price also includes tax and shipping. It also looks like I can throw in a sticker with each t-shirt order. Sweet! This $20 also goes toward the cost of the blank shirt, printing, mailing envelopes, and labels (mailing and return).

$2.50 gets you a high-quality sticker. This covers the cost of getting the sticker made, the envelope, labels, and postage. Of course, if you order two or three stickers, it's a better deal.

*Important note: my buddy Johnny from Speysyde was in charge of printing the t-shirts and he did a fantastic job! Please cruise by his site. It's all about the sustainable lifestyle:
Our mission is simple. To spread awareness and advocate an eco & social sustainable lifestyle through the creative collaboration of culture, music, sport, art, adventure & travel.
I declined using some of the premium web store features my host offers, such as shipping calculators, tax calculators, and other premium web store features. This drastically keeps the cost of the shirts at $20. For each purchase and transaction, Stripe takes a small percentage from my side. There is no additional cost to you. Their service, similar to PayPal, makes each transaction secure, safe, and easy.

I think you'll truly enjoy your shirt. I am!


Wednesday, July 2, 2014

Barbie Zip Line

Inspiration from Matt, John, and Jedidiah helped me shape my Barbie Zip Line task today. Whenever I prepare new tasks for my students, I have been trying to keep mathematical modeling, student ownership/creativity, performance tasks, and openness in the back of my mind. That's a lot, right? Plus, there's a hundred other little things, but let's focus on the list above. As I reflect on today, I'll share how I would improve this for next time.

Supplies (in order of attachment):
  • Barbie doll, or an action figure like G.I. Joe, Superman, or Captain America
  • Velcro: One-wrap (don't get Sticky Back)
  • Carabiners
  • Swivel Spring Snap (optional)
  • Fixed Pulley
  • Rope (thin enough to fit through the pulley)
My first piece of advice after learning from today: don't skimp on the pulley system. I made two and I should have made (bought) more. I would spend the money and have enough pulley systems for the number of groups you plan on having. Second, you could connect the pulley straight to the carabiner and avoid using (buying) the swivel spring. Third, velcro (harness) is the best way to quickly attach your pulley system to the zip line rider.

Buy enough rope so that you can have lengths that are 10 feet apart. In other words, have different rope lengths: 30 ft., 40 ft., 50 ft., 60 ft., etc. This will play well into the mathematical modeling part of the task (see below). It will also help make it easier to get the pulley systems on and off of the zip line. Solving the task yourself will also help determine the rope lengths you'll need for your school site.

The task (handouts found here):
Depending where (and who) you teach, some students have been zip-lining before. Ask! It never hurts. Maybe they can share their experience. Plus, this gives you a chance, at some point (if you feel necessary), to talk about how they're sitting in front of you, ALIVE, because someone was able to do some solid math and build a sound enough structure for them to zip line on. Just sayin'.

I low-balled my students today on their budget. I should have raised it to $2500 or $3000. Figure out what will work for your site. However, this mistake allowed me to give some early finishers an extension: find a more reasonable starting budget.

Here are the opening costs of your zip line company:
Students had to receive approval from their Summer Academy principal by showing their designs. I highly encourage this move. Students see someone else taking a vested interest in their learning. The principal gets an informal glimpse of your classroom. And students have to be prepared to explain the math and their problem-solving approach. If your principal is unavailable, get someone else: teacher, custodian, campus security, etc. It could be you, but you're already doing the formative approval (assessment) in class.

All these prices can change depending on your tastes. I included a liability insurance just for fun. The materials for the harness and pulley system need to be of high quality, so don't make them cheap. $50 might have been too cheap. The most important material is the steel cable (rope). This will help create multiple solution strategies. It's beautiful. Overall, I was pleased with my price points.
I found that having students create three rides is essential to this task. At least three rides. Sometimes tasks generate such a strong focus on the ONE CORRECT WAY to construct an answer or problem-solve. This adds pressure and can rob students of discovering mistakes or playing around with numbers. By creating separate zip lines for both certain death and boredom (getting stuck), it does many beautiful things.

Students innately know what type of zip line would kill barbie: a steep zip line. They can sketch that on their whiteboard, no problem. On the flip side, students have a good understanding of a boring zip line: practically a horizontal line. They can also sketch that on their whiteboard. Both sketches can be done without using numbers, formulas, or mathematical notation. It creates an entry point for all students. So here's what they had to say:
Leyla: We have a chance to see what not to do.
Trevor: It reminds me of when we do Estimation [180] and you ask us to give a too low and too high. It helps us find a reasonable number in the middle.
Deena: It shows us what a wrong answer or zip line would be.
Students were able to draw steep zip lines, label the height 20 feet, guess the ground distance to be about 5 or 10 feet, and use the Pythagorean Theorem to calculate the length of the cable (hypotenuse).
Mathematical Modeling and Multiple Solutions:
Students were able to design their own zip line by playing around with the numbers between their certain-death zip line and boring zip line. I told them to dream big on the whiteboards as if money wasn't a factor right now. Most did. Most.

I had a couple groups first figure out the cost of all the materials ($700) and subtract it from the $1500 budget, giving their group $800 to spend on cable. With $20/foot, they could use 40 feet of cable for their zip line. They identified the height and the hypotenuse of the right triangle. Impressive.

One of these two groups felt this wasn't enough cable and it was still too steep. Michelle had been zip-lining in real life so she knew. This was my mistake, but it turned into an opportunity for me to extend this task. I asked them to create a new budget for me so the cable was longer, but within reason. If you need more of an extension, have them come up with a formula to determine the amount of cable and distance on the ground, given a specific amount of money.

Before they could go outside and test their zip line, students had to complete this list:
I had students transfer their work to their graph paper composition books before they took it to the principal. I'll insert some pictures:

Here's the permit:

It was a blast! Students loved it. Here's another extension:
Have students design a system that gets the pulleys and/or dolls back up to the top of the zip line.

[insert video here]

By the way, I did teach the Pythagorean Theorem in there somewhere. Where? You might ask. I don't remember: ALL throughout the task. Use discretion. Some students need it first. Some need it after you've let them mess around on the whiteboards.