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In 2018 I semi-retired by retiring from Weston High School after my 21st year teaching mathematics there. This was also my 44th year as a teacher altogether. In 2023 I retired fully, adding in my 18 years at Harvard’s Crimson Summer Academy each summer. For 21 years I had taught at the Saturday Course in Milton, MA, and I used to serve on the board of the Dorchester Historical Society.

I read, cook, and spend a lot of time building my model railroad. For some reason I’m left with less free time than would be ideal, considering that I’m supposed to be retired, but somehow I also manage to devote time to my wife, Barbara, and to our varying number of cats (once up to six, but now sadly down to one).

Larry Davidson
ljd@larrydavidson.com

  • Do negative numbers exist? And why do two negatives make a positive?

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    A brief interchange on Facebook yesterday and today with three of my former students prompted this discussion of the two questions stated in the title of this post. It all started with this implausible claim from a reliable math website:… Read More ›

  • New York 2140

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    Most good science fiction takes a single premise (which may or may not be believable) and spins out the consequences of that premise. To be convincing, there should just be that one premise, since most readers are willing to suspend disbelief… Read More ›

  • School of Rock

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      I really didn’t think I would enjoy this movie. “Not my style,” I said to myself. But I was wrong. Although it’s true that it is not my style, I still enjoyed it a lot. In case it’s not… Read More ›

  • A portal for parents

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    There’s an excellent article in last week’s New York Times on the downside of checking kids’ grades constantly through an electronic portal for parents. Here are a couple of excerpts: The reality, at least in high-pressure school districts, is that some parents… Read More ›

  • I Know a Secret

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    Don’t read Tess Gerritsen’s newest Rizzoli and Isles novel, I Know a Secret, if you (like someone I know) are prone to having nightmares based on books and movies. The rest of us will find it fascinating and suspenseful. To a large… Read More ›

  • “If it ain’t broke, don’t fix it?” (Rethinking quadrilaterals)

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    Why on earth would we spend two whole days rewriting our Honors Geometry quadrilaterals unit? Our textbook, after all, contains a perfectly serviceable sequence of four lessons on this topic: These lessons are adequate. In the words of the standard… Read More ›

  • New furniture!

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    Arrived yesterday to find new furniture for students to use in our Math Office. As you can see, the chairs have wheels and the tables are modular (eight of them, though not all are visible in this photo). This combination… Read More ›

  • Coding in middle school math

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    Google Blockly? What’s that? And should we say coding or computer programming? We’ll deal with that terminological question in the last paragraph, but let me first tell you about Blockly and about the workshop we had yesterday. A group of… Read More ›

  • Confessions

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    This psychological thriller by Kanye Minato is not a typical book, at least not in my universe. Some say that it’s a lot like Gone Girl — but I wouldn’t know, since I’m apparently the only person on Earth who hasn’t read Gone… Read More ›

  • Don’t get lost: mark your place!

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    Who uses paper maps anymore? At least they can be recycled, but what if they’re already laminated? Barbara sliced one apart and turned them into bookmarks!

  • Watermelons?

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  • Damaged

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    If you’ve never read any of Lisa Scottoline’s South-Philadelphia-based Rosato & DiNunzio thrillers, Damaged would not be a bad place to start. (Note: I really like all the Rosato & DiNunzio books, though I don’t particularly recommend Scottoline’s so-called emotional thrillers. But maybe… Read More ›

  • Standards-based grading?

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    What’s wrong with grading on a curve? Or what’s wrong with grading by straight percentages? Twelve years ago I wrote a post about why grading on a curve is destructive and counterproductive — and why grading by straight percentages isn’t actually… Read More ›

  • The Fight for English

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    It seems that I have to write about David Crystal once a year or so. This expert popularizer of linguistics always provides well-informed but accessible antidotes to common myths about language, such as the one alluded to in the subtitle… Read More ›

  • Back from Manchester (but which one?)

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    No, not that one! Not Manchester, New Hampshire. Not Massachusetts. (Oh, you’re right, that one is now “Manchester by the Sea.“) Not Connecticut. Does every state around here have its own Manchester? Not even Manchester, England. (Or do I mean “Manchester,… Read More ›

  • The War Room

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    How I miss Bill Clinton! Yes, he certainly wasn’t a perfect president — and yes, he wasn’t Obama — but… [You can finish the rest of the sentence yourself.] The War Room is a documentary about Bill Clinton’s successful 1992 campaign… Read More ›

  • Morning glories

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    I do love our purple morning glories!

  • Ben X (a film about Asperger’s)

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    Grim. Much too grim. I’m talking about Ben X, a subtitled 2007 Dutch-language movie from Belgium — a work of fiction, based on a real story. I don’t have any problem with serious films, but I just had to stop watching Ben X half-way through…. Read More ›

  • Hillbilly Elegy

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    What an irritating book! Even if you haven’t read Hillbilly Elegy by J.D. Vance, you’ve probably at least heard of it, as it made quite a splash when it came out last year and stayed on the best-seller list for weeks… Read More ›

  • Unseen World

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    Unseen World, a fascinating and complicated novel, will capture and maintain your attention — if you’re the right sort of reader. Right for this book, I mean of course. You probably are if you’re interested in computational linguistics, artificial intelligence, online virtual worlds (as… Read More ›