Sunday, March 2, 2025

Mathish-ish

 Read Jo Boaler's Math-ish and thought it would be useful to pull out the valuable points and provide an overview of the rest.

Encourage Metacognition Through Eight Mathematical Strategies

This is from page 39-45. I'd note that this set of ideas is somewhat typical for the book: though described as methods to encourage "metacognition," these are closer to problem solving strategies.

This list is populated with ideas that will be familiar from other standard sources, like Polya's How to Solve It or Cuoco's Mathematical Habits of Mind. Nonetheless, these are still solid cues for a teacher/tutor to either help with the problem solving process (1, 2, 3, 5, 8) or to move beyond simply finding a right answer (3, 4, 6, 7.)
  1. Take a step back
  2. Draw the problem
  3. Find a new approach
  4. Reflect on "why?"
  5. Simplify
  6. Conjecture
  7. Become a skeptic
  8. Try a smaller case

Reflection cues

From page 48, a quasi-infographic with seven cues that are actually directed toward metacognition. 
  1. What mathematical concepts did you learn today?
  2. How is the idea you learned today related to others you have learned?
  3. What opportunities did you get to struggle? How did that feel?
  4. How could you use the mathematical concept in your life?
  5. What different strategies or approaches to the problem were helpful to you?
  6. Are there areas that you do not understand and would like more opportunities to learn?
  7. Can you write your own problem for someone else to try to solve?
Boaler suggests asking students to answer one of these questions, of their choice, in place of standard homework problems. From my personal experience, it takes consistent effort to get students to take these reflection questions seriously.

Group work

Initially, I noted two blocks in this section (pages 52 and 53): a set of 5 roles during group work and 8 "mathematical ways of working." On returning to this discussion, I was more struck by the things that Boaler does not cover related to group work. In particular:
  1. The critical importance of finding activities that truly require group engagement and cooperation.
  2. The typical level of frustration that most students associate with their prior group work experiences.
For example, of the 8 "participation quiz" behaviors, only two of them somewhat depend on the group (underlined and bold):
  • Recognizing and describing patterns
  • Justifying thinking using multiple representations
  • Making connections between different approaches and representations
  • Using words, arrows, numbers, and color coding to communicate ideas clearly
  • Explaining ideas clearly to team members and the teacher
  • Asking questions to understand the thinking of other team members
  • Asking questions that push the group to go deeper
  • Organizing a presentation so that people outside [the group] can understand your [group's] thinking

Struggly

Boaler advertises a website, Struggly, that seemed worth investigating. It maybe hard to get a full sense from the demo activities, but I didn't see anything either bad or special here. If other people have used it, please let me know what is unique about Struggly (in comparison with ST Math, for example.)

Integrating math history

Boaler cites (page 86) several aspects in the history of Fermat's Last Theorem and Andrew Wiles' proof:
  1. The vast amount of valuable ideas that emerged in the course of attempts to prove FLT
  2. The fact that Wiles' initially announced proof had a gap
  3. The way that professional mathematicians persistent through their work over extended periods of time
Personally, I do find it tempting to incorporate biographical and historical information in math classes, but I don't think I have found a way to do this that fully resonates with students or has the effect that I want.

What matters in pre-college mathematics

I'm on board with the idea that only a small number of key concepts from pre-college mathematics are really critical for students and a sharp distillation is helpful. Starting on page 95, Boaler identifies three candidates. For what it is worth, the source is David Coleman, the CEO of the College Board. In general, the College Board doesn't seem a force for good in education, but these three candidates seem plausible.

Number sense/arithmetic

An ability to calculate with basic arithmetic operations, an understanding of fractions, and a sense of estimation. Here is where Boaler really hits her "ish" concept, an acknowledgement that almost all real-world incarnations of mathematical concepts are approximate, rather than exact.  I would prefer to broaden this a bit and say that strong number sense should include an ability to switch between the approximate and precise and a recognition of the differences between them.

Data literacy/Data analysis and problem-solving

In this section, Boaler rehashes the (now) obvious point that data is abundant and students/citizens should have some facility to interpret and analyze data.  Some nice visualizations are included:
  • Stephen Curry's 2015-2016 shot performance (page 124)
  • NCAA Women's Soccer PSxG for penalty shots (page 125
  • Examples from dear-data.com
  • Student data representation from the student's life (page 127)
The youcubed data science course: https://hsdatascience.youcubed.org/curriculum/
I will try to find time to review that specifically.

Linear Equations

This section does not really justify why linear equations have a distinguished place in the top 3 concepts.  I may return to this to back-fill potential reasons, but most of what is cited (pages 129-131) is spurious, rather than real linear relationships.

Fractions

Visual representations of 1 ÷ (2/3):

In several parts of Math-ish, Boaler emphasizes the importance of understanding fractions, in contrast to a rote/algorithmic approach to calculating with them.  I think these visual representations are the best thing she offers as a step toward ways of understanding.

Sunday, July 3, 2022

Korean Air (according to google translate)

A survey request from our recent flight:

대한항공과 함께 즐겁고 편안한 여행 하셨는지요?

고객님의 소중한 의견을 듣고자 설문조사를 실시하고 있습니다. 잠시만 시간을 내주시면 감사하겠습니다.

We hope you had a pleasant trip with Korean Air.

Please answer this short survey to share your valuable feedback with us.

邀请您参与简短的问卷调查,与我们分享您的宝贵意见。

サービス品質向上のためのアンケート調査を行っております。ご協力お願い申し上げます。


The Korean text (according to google translate, my emphasis added):

Did you have a pleasant and comfortable trip with Korean Air?

We are conducting a survey to hear your valuable opinions. Thank you for taking a moment.

The Chinese text (atgt,mea):

You are invited to participate in a short survey to share your valuable opinions with us.

The Japanese text (atgt,mea):

We are conducting a questionnaire survey to improve service quality. Thank you for your cooperation.

Perfect numbers: Lichtman's Theorem (Part 1)

This summer, we are working through Jared Lichtman's recent proof that the primes achieve the maximal Erdős sum over primitive subsets of the natural numbers.

Quanta Magazine had a very nice article describing the theorem (formerly a conjecture of Erdős) which is the inspiration for this project. The article is here.

I will be posting notes on our conversations. The most important thing to understand: this project is about the journey and not the destination. We may not (probably won't!) get all the way through the paper. Along the way, we will take plenty of detours and excursions.

Wednesday, August 11, 2021

Possibilites for G4G

  1. misère version of go problems
  2. slinky tangles (more seriously, links with secondary structure for alpha-helix protein folding) 
  3. caesar cipher rotations: inspired by this which was probably mentioned on ACX or DSL
  4. Chebyshev machines with mindstorms
  5. multi focus version of ellipse (constant string length)

Monday, December 28, 2020

Queen's Gambit comments

Putting this here for no particular reason.

Queen's Gambit: B+/B. Entertaining, with some issues.

 

1. 

The ending was too perfect, but we knew something like that would happen from nearly the first scene (as soon as we knew Borgov's name). I wonder if it would have been better with a slight twist: if the final game had been a legitimate draw. Probably the general audience doesn't know this, but it is (now) very common for top level chess matches to end with a draw.  I'm not sure how common that was in the 60s.


To support that result, they probably would have had to lay a bunch of groundwork earlier.  maybe a game with Shaibel that ends with a drawn position and he has to explain why it isn't worth continuing to play? As it is presented in the show, a draw is just a trick, when one player thinks they have lost, but they think the other player doesn't see how to win, then they offer a draw as a psychological play on the lack of confidence.


2.

They did, eventually, address all my major issues (drugs, genius). Also, the way they set up the team support was well done.  First, they show us that the soviet players are collaborating.  The audience  probably thinks that's cheating, but it serves to legitimize the support from the US players (which, as depicted, is pretty implausible, since it involves exactly the 6 serious male players who have appeared more than once).  Then, during play, Borgov deviates from the ideas the team had considered, so we see that Beth actually does win "on her own."


3.

By coincidence, I just read The Big Bounce, a novel from the 60s.  One theme of that book was "women are bored and unsatisfied with life, have to turn to substances or craziness to occupy themselves." It is very condescending.  Unfortunately, there were also echoes of that in TQG: Beth herself, the society girl from high school, Beth's bio and adoptive mothers, Cleo.  Jolene and Packer(? the woman from the first chess tournament) are exceptions, but they don't get much screen time in those roles.


Perhaps would have been nice to see more of her bio mother. I didn't really understand what was going on with her, so maybe she was trapped. Didn't seem that there was anyone trapping Alma, the adoptive mother. There were nods to the idea of some generalized social pressure (the first Life interview, the society club high school student, the two women getting paired in the first tournament), but it was all pretty diffuse.  For example, we didn't ever see any US Chess Federation opposition to Beth playing in the open division for the US championship.


4.

Other misc thoughts: 

(1) Beth's affection for Townes doesn't really ring true.  Fine that she had a crush on him for a while, but I didn't buy that it was a deep love simmering for years and years. 


(2) I didn't understand the lack of consistency in the post-sex scenes between Beltik and Benny. In the first, Beth is shown to be cold because she is immediately thinking about chess, but, in the second, she is shown not comprehending that Benny would immediately think of chess afterwards.  


(3) Cleo says (and Beth seems to agree) that Benny is only in love with himself. While we definitely see that he thinks highly of himself, he has clearly gone out of his way to help Beth, for no discernible benefit to himself.


(4) The Cleo sabotage evening had several things that didn't sit well.  First, Cleo knows that Beth has a big day ahead and completely undermines her. It was such an extreme degree that I almost thought there would be a reveal of Cleo getting paid off by the Russians or some other group opposed to Beth. Second, it shows Beth waking up in the bath. Could that possibly be a thing? If she were so unaware that she wouldn't notice the discomfort, wouldn't she drown?

Saturday, May 16, 2020

Chinese and Weiqi (go) videos

A collection of videos for studying go and chinese together, for J1:

— Beginning level tutorial, this series is made almost 20 years ago, classic but outdated (https://www.bilibili.com/video/BV1ZW411h7Mf?from=search&seid=14516269619931393154)

— Beginning to mid-level life-death problems ( https://www.bilibili.com/video/BV1Rx411Y79F?p=1)

— Bad moves analysis (in Chinese literally translate to ‘smelly’ or ‘stinky’ moves) (https://www.bilibili.com/video/BV1cJ411w7bz?p=1)

 — Ancient complicated life-death problems from the 1700s, some are doable, some are so massive and even challenging for pros (https://www.bilibili.com/video/BV17x411x7hL?p=1)



  Ke Jie’s 15 best games voted by fans https://www.bilibili.com/video/BV1BW41177kC?p=1

— Pro game, commented by Ke Jie (https://www.bilibili.com/video/BV1kJ411x7bZ?p=1)

— AlphaGo VS AlphaGo 50 games (https://www.bilibili.com/video/BV1ob411e7DN?p=1)




— CCTV (China Central Televison) ‘s documentary about weiqi (https://www.bilibili.com/video/BV1s4411B7Np?from=search&seid=2724260708536054014)




Tuesday, February 11, 2020

What is 8?

I've had a chance to spend more time doing math with the kids again and am hoping to write up our activities more consistently.  Let's see how this works out!

Graham Fletcher created a set of  Progressions videos for various elementary school themes. J3 and I recently went back to his page and found he had a new(er than we knew) progression on early number and counting.  Even for this simple topic, the video highlights some points we hadn't considered explicitly, for example distinguishing producers (of a number) and counters. Also, the cardinality point that smaller natural numbers are nested within larger numbers wasn't something we had talked about, but we soon realized it was part of many examples in how we understand numbers.

With that as inspiration, J3 and I decided to search for a range of examples of a single number, we chose 8, in different forms.  There is at least one obvious version we're missing.

Add a comment (with picture, if you can) to show other forms of the number 8!

Marking 8 on the 100 board, an easy place to start:



8 beads on the abacus shows the relationships 3+5 = 8 and 10-2 = 8 (also 100- 92 = 8)

8 can hide in plain sight. Without labeling the three lengths, it would have been hard to recognize the longer one as 8 cm and, for you at home, impossible to know without reference to show the scale.


It happened that, within the precision of our scale, two chocolate wrapped chocolate bars were 8 oz (2x3.5 oz of chocolate + about half an ounce of wrapping for each):

8 cups of water ended up being a lot, so this version unintentionally revealed a relationship 4 + 2 + 2 = 8

Though I'm not sure I can articulate why or show supporting research, I feel it is very valuable to build experience with physical models of numbers to create familiarity and intuition about what they are/mean. In particular, I hope this helped J3 anchor the importance of units of measure and scale in the interpretation of numbers.

Finally, this construction has nothing to do with the number 8 (or does it???)