Google Blockly

From @joshgiesbrecht , fantastic web app from Google. Blockly is a web-based programming environment that allows you to export the code as Python, Javascript, Dart (anyone outside of google use this??), or XML (wow ugly code).

Blockly was just released a couple of days ago so it’s still rough around the edges, but has a nice intro assignment: Solve the maze. Here’s my solution which should work for simple mazes. It’d be nice to change the maze around or to save your code, but these features are not yet implemented.

Here’s an example for the blocks being translated into nice pretty Python code. Awesome. I’ll use this an an intro to text-based languages next year.

The thing that worries me about Blockly is the usual stuff with Google. Will it be developed or will they let it die on the vine? Will it be dropped after a couple of years because the developers found a shinier toy to play with? Oh well.

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Timon on 101qs.com

Timon Piccini has been kicking ass at this math blogging thing for a while now. Here’s part of his take on Dan Meyer’s 101qs site:

Over at Dan’s site people have been discussing these last set of questions and we find, naturally, Dan promoting his brand of “Make the prompt scream the question you are looking for” and Karim Ani saying, “There are more interesting questions that go beyond a one minute clip or picture.”

I think many of us, including Dan and Karim, find ourselves right in the middle of these two conflicting axioms. On one hand we desire that students seek for themselves. We desire that they personally invest in interesting questions that provoke grand thoughts about life the universe and everything. Yet we also recognize that they are young whippersnappers who have little experience beyond their hometown, school, and even neighbourhood; they may not have the capacity to think beyond the world of their home. We then as teacher must make the hard decision of how to lead them to these wonderings.

From Timon Piccini’s take on 101qs.com.

Read his other posts too. Or else.

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Taking the ACT a quarter century after high school – Scott McLeod

Interesting read.

My biggest concerns about the math test relate to the fact that much of what is assessed is math that – and I think I’m safe saying this – most of us will never use again (how many of you have needed to calculate the cosine of an angle recently? how many of you have needed to determine the formula of a circle on a standard coordinate plane?).

It just bothers me a great deal that we’re herding many, many students through math classes that are largely irrelevant to their future life success (most high school students don’t get much probability and statistics, for example, even though that’s what I think they’ll need most often beyond foundational numeracy).

Analogy: How many touchdowns did Herschel Walker score in the NFL for his 3,500 situps and 1,000 pushups a day workout routine?

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The Love Tree – A Math Puzzler (?)

From Car Talk.

A teenage boy smitten with a teenage girl in his high school freshman class, made his feelings known. Overjoyed at finding them reciprocated, he took pen knife to a young hard wood in the vicinity and carved their initials within a heart, five feet up the tree’s trunk.

By their senior year, however, the girl’s ardor had cooled. She took her diploma, went away to the big city and married. The boy was crushed, inconsolable.

Bidding his family farewell, he took his small savings that he got from selling lemonade, bought a bus ticket, went to the east coast and shipped out in a menial job on a broken down freighter.

Twenty-five years later, captain of his own vessel, owner of a small freighter fleet and with a major interest in a few oil tankers, he indulged in a nostalgic whim and returned for the first time ever, to his old hometown.

Imagine his joy, when he discovered his old sweetheart living there, now a widow.
One thing led to another. The flame reignited, and one day they searched for their tree. It was not hard to find. It was near a rock, near a river, and they immediately found it.

Now, here’s the puzzler. If the tree had added 35% to its height in the first 15 years of his absence, 10% in the following in the five years and 2.5% in the ensuing eight years, how far up the trunk did they have to look to find the carving with their initials?

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MegaMillions Jackpot

The estimated payout for the MegaMillions Lottery on Friday is $476,000,000, the highest payout ever for MegaMillions.

Does it make mathematical sense to buy a ticket today?

From the How To Play website:

Interesting stat in the news article that allows you to figure out how many tickets were sold for the last drawing:

The odds of winning any of the Mega Millions prizes are approximately 1 in 40.

The estimated jackpot is based on national sales up to the time of the drawing. In the last drawing, in which there was no jackpot winner, almost 2.9 million tickets won Mega Millions prizes.

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Coaching vs Teaching

I’ve been coaching hockey and teaching math for around 8 years. I thoroughly enjoy the contrast of the two positions. But I’ve slowly noticed that there are many strategies in one job that carry over to the other.

Here are some points for what makes a good hockey practice and a good hockey game.
The corresponding teaching strategy are in italics.

Practice

    • “Chalk time” is minimized (possibly done before getting on the ice, icetime is expensive), and players actually executing drill is maximized.
      Traditional models of teacher-centered teaching should be replaced by student-centered activities in most cases.
    • The number of players moving during a drill is maximized; the worst drills have only a couple of skaters moving. The best drills have a quarter to a third of your players moving. Ideally you’d like to have a work to rest ratio of around 1:2 for a practice (for every 1 minute of work, there is 2 minutes of rest).
      Students high-ability and low-ability should be busy during a lesson. A group of strugglers should not drag down the speed of a class just like a group of high achievers shouldn’t speed up a class. Ideally, if you imagine the students on treadmills, there is no reason for the speed of the treadmills to be constant among all the students.
    • All movement is done at full speed, there may be hestitaiton if the drill is new, but after the players get used to the drill they should be moving at “game” speed. You play games like you practice, so the faster you move in practice leads to fast movement in a game.
      Students are pushing themselves to their limits. They aren’t happy with just barely getting by, and aren’t happy to cruise at a level below their optimal level.
    • Drills emphasize specific hockey skills and the players know what skills they are working on in that drill. But they do not stop being hockey players; they must not abandon good hockey skills to just complete the drill.
      Students should know what skills they are improving during a class. They should be focused on learning that skill. But they must also solve these skills in an environment that is as realistic as possible. Less abstraction, more detail.
    • Players are exhausted at the end of the practice, physically and hopefully mentally. They were asked to go to their own personal limit (even if some players have different limits compared to others). Players in great shape should be pushed equally to their limit as weaker players.
      Everyone should be pushed to improve. High and low achievers both.
    • The coach is running the drills, may demonstrate specific portions of the drill, but team instruction is minimal (talking to the whole team when one players made a mistake), and buy prednisone 20mg tablets individual instruction is ideal (one on one conversations). How many times has a coach yelled at the whole team for an individuals mistake? I hated that, and as a coach, I try not to make that mistake myself.
      “Everyone can’t factor this quadratic, you should know this” isn’t normally the best way to approach changing behavior. Don’t you hate it when your administration addresses the entire faculty for the faults of a couple teachers?

Gametime

    • Players are excited but relaxed. Amped but in control. Prepared for the game but ready for anything.
      Students are flexible under pressure. Able to stay loose and show what they know and not freeze up.
    • Players have a short memory but a long vision. Mistakes don’t snowball. Luck is not mistaken for a proper play.
      Even if students get a multiple choice question right by guessing, they understand that they need to be able to solve it without luck.
    • Players are relentless in their effort, from the puck drop to the buzzer. They start a game right, and they finish a game right.
      Students don’t have off days, when an assessment given out, they are ready to go.

Thoughts? Overreaching?

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Follow-up to 25 billion apps

Follow-up to 25 billion apps. Our class calculated that the app store would hit 25 billion on Friday at 11pm eastern. The contest is over, but the press release didn’t say when it finished.

The 25 billionth app downloaded, Where’s My Water? Free, was downloaded by Chunli Fu of Qingdao, China. As the winner of the App Store Countdown to 25 Billion Apps, Chunli Fu will receive a $10,000 iTunes® Gift Card.

So I emailed Apple PR with little hope of actually getting a response.

An hour later I get the following from Ted Miller from Apple PR:

Hi Daniel,

Thanks for reaching out. That sounds like a fun idea for the class!

We officially reached the milestone around 10:50pm PST Friday night.

Best,
Ted

Ted Miller
Apple PR
408-862-3928
ted_ miller@apple.com

Sent from my iPad

So we were off by 3 or so hours, but my tough group of students were really engaged.

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Light Limaçons and Cardioids

While putting away the bowls, I noticed some nice limaçons and cardioids made from the refraction of light.


Video of the changing shape – Limaçons

 

For more info:

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