David Flynn @dpfl.bsky.social · 07/02/2025I picked one of these up at a car boot sale a few years back with honest intentions to learn how it worked but never got round to it. 010
David Flynn @dpfl.bsky.social · 03/02/2025Though example 1 isn’t a particular good “e.g” in this case. Oh dear. 000
David Flynn @dpfl.bsky.social · 03/02/2025That’s a great question and something I completely overlooked. Derangements only seems like a necessary rule to make this question interest, but the first example doesn’t use that. 210
David Flynn @dpfl.bsky.social · 09/01/2025Honestly I can’t either anymore. I probably made a mistake but I’m gonna believe I had a moment of insight that’s just forever lost. 010
David Flynn @dpfl.bsky.social · 08/01/2025This looks interesting. What are the common errors you’re referring to? 100
David Flynn @dpfl.bsky.social · 24/12/2024Maybe gradually removing parts and asking they think goes in the blanks. 100
David Flynn @dpfl.bsky.social · 24/12/2024Nice problem. I wonder if there is a way to keep this engaging for the kids after they’ve noticed the pattern. 200
David Flynn @dpfl.bsky.social · 20/12/2024Storytelling about *learning* math is a lovely way to reframe perceptions of what is means to be a math person. 030
David Flynn @dpfl.bsky.social · 19/12/2024Is there something specific you’re talking about with number sense and fractions? 100
David Flynn @dpfl.bsky.social · 19/12/2024I think there’s also a lot with can do with digital representations that help strengthen conceptual understanding. 010
David Flynn @dpfl.bsky.social · 19/12/2024This is a good read! Looking forward to reading a few more responses on this one. #mtbos #iTeachMath 020
David Flynn @dpfl.bsky.social · 19/12/2024I think remainders in grade 4 can be really messy and not always done well. For example: 16 divided by 5 is 3 remainder 1 25 divided by 8 is 3 remainder 1 But 16 / 5 =/= 25 / 8 All in the same grade where students learn that 16/5 = 3 1/5. 010
David Flynn @dpfl.bsky.social · 19/12/2024That’s grade 3. There’s a lot of high impact stuff in Grade 3, particularly multiplication and fractions. A lot of struggles start if students are learning multiplication disconnected from addition, and fractions disconnected from integers. 010
David Flynn @dpfl.bsky.social · 18/12/2024The base 10 blocks play an important role. Altogether we have 182 blocks, but we can’t just make *any* rectangle with area 182 since the 100-piece won’t allow it. 010
David Flynn @dpfl.bsky.social · 18/12/2024What’s the max number and what’s the min number is a great prompting question for this. I wonder if aiming for a sum of 0 initially sounds like more of a challenge to students - when in practice it’s slightly simpler. 010
David Flynn @dpfl.bsky.social · 15/12/2024Nice question, started working on it before seeing the area of 2 condition so had to go back. I’m struggling to find the rhombus that isn’t a square. 220
David Flynn @dpfl.bsky.social · 15/12/2024That sounds pretty convincing. What about something like 32 and 55? 15 hundreds 25 tens 10 ones There are 2 different rectangles I can make with those blocks. 110
David Flynn @dpfl.bsky.social · 14/12/2024I meant giving “= 7/18” on F and “= 2/7” on G. It might shift the focus from evaluating the expressions to thinking more about the patterns - why sometimes the denominator changes and why sometimes the numerator changes ¯\_(ツ)_/¯ . But if the goal is evaluation - this’d make the task worse. 000
David Flynn @dpfl.bsky.social · 14/12/2024I absolutely love this task. But I wonder if it suggests we’re not allowed to say 7/9 = 3.5/9. Do you think the task gets better or worse if you changed from expressions to equations? 110
David Flynn @dpfl.bsky.social · 14/12/2024Maybe you could try some open number line stuff with division? And then revisit it when you get to fractions. I put together this task with 24 (which is nice for connecting to 3rd grade denominators!) You can use the first task during division, and then try a similar task during fractions. 120
David Flynn @dpfl.bsky.social · 14/12/2024Another example of a unique solution: Put together 2 hundred-pieces 21 ten-pieces 27 one-pieces to make a rectangle. An example of a non-unique solution: Put together 1 hundred-piece 7 ten-pieces 10 one-pieces to make a rectangle. #MTBoS #iTeachMath 040
David Flynn @dpfl.bsky.social · 14/12/2024Puzzle for 4th Graders: Using Base 10 blocks, put together 1 hundred-piece 7 ten-pieces 12 one-pieces to make a rectangle. What are the side lengths of your rectangle? Puzzle for #iTeachMath #EduSky folks: What are the considerations in number choice that make these puzzles unique vs. non-unique? 4142
David Flynn @dpfl.bsky.social · 14/12/2024What are the things that are most scary about teaching fractions? Are there things you find that students particularly struggle with? 100
David Flynn @dpfl.bsky.social · 13/12/2024Am I suppose to write a number in each arrow or square? 100
David Flynn @dpfl.bsky.social · 13/12/2024I thought impossible at first too. If A x B = A / B then has to be 1 (or so I thought). In which case both of the expressions are equal to A. In which case, A + B is A + 1 which doesn’t work. ☹️ Then I thought about whether B might be -1 🤔 000
David Flynn @dpfl.bsky.social · 12/12/2024I’m not sure what the best set of divisors are for this task. Including 5 and 9 definitely make the solution more interesting. But having 5 divisors make the task too cumbersome for primary school learners.media.tenor.comkermit the frog and miss piggy are kissing each other in a muppet show .ALT: kermit the frog and miss piggy are kissing each other in a muppet show . 010
David Flynn @dpfl.bsky.social · 12/12/2024Nice. The elegance of that solution seemed to me that 335 must be the smallest number where we can max out the remainders. But 167 works similarly well. 100
David Flynn @dpfl.bsky.social · 12/12/2024Glad I saw some other responses before wishing you a happy 76th 👀 110
David Flynn @dpfl.bsky.social · 12/12/2024Pick a 3 digit number. Divide the number by 6. Write down the remainder. Divide the number by 7. Write down the remainder. Divide the number by 8. Write down the remainder. Add the three remainders together. What starting number should you pick to get the greatest possible sum? #iTeachMath 283
David Flynn @dpfl.bsky.social · 12/12/2024Beast Academy is the ‘elementary’ wing of AoPS. But it covers a lot of middle school stuff. The Level 5 books get fairly advanced. 130
David Flynn @dpfl.bsky.social · 11/12/2024When students start estimating in grade 3, the standards ask them to do it with problems that can be solved exactly. It can feel contrived. Fermi problems are a great way to introduce estimation in a way that’s authentic, fun, and slightly divorced from all the arithmetic done throughout the grade. 010
David Flynn @dpfl.bsky.social · 11/12/2024This is also a great example of why number choice matters so much. 020
David Flynn @dpfl.bsky.social · 04/12/2024Left one: How many different sized squares can you see? 020
David Flynn @dpfl.bsky.social · 04/12/2024I think similar but slightly different question that I find interesting whether or not folks include the subject they teach when they’re asked what they work as. “I’m a teacher” Vs “I’m a maths teacher” 121
David Flynn @dpfl.bsky.social · 27/11/2024It took a bit of trial and error to figure out if any area was uniquely solvable. I think/hope that it is. 000
David Flynn @dpfl.bsky.social · 27/11/2024As a follow up to this Dot Puzzles. I was thinking about how we can use this same set up with fractions in 3rd Grade. Here's a very rough mock up of a puzzle format: #iTeachMath #MTBoS #mathstoday 162
David Flynn @dpfl.bsky.social · 27/11/2024Oops! Unsolvable.media.tenor.coma cartoon of homer simpson standing in a grassy areaAlt: a cartoon of homer simpson standing in a grassy area 100
David Flynn @dpfl.bsky.social · 27/11/2024Let me know if you get an answer. I *think* there is only one unique solution. 100
David Flynn @dpfl.bsky.social · 27/11/2024More confusingly, they go by *both* names in the standards. 000
David Flynn @dpfl.bsky.social · 27/11/2024I like this! But I do wonder how natural the connection is from multi step word problems to order of ops. “Berkeley has 6 cookies on his plate. He gets another 3 plates with 5 cookies on each, how many cookies in all?” Answering this question? Sure 👌 Writing an expression? Yikes 😬 110
David Flynn @dpfl.bsky.social · 27/11/2024I don’t *think* it does. I remember cheesing a template on PowerPoint years ago when I wasn’t able to use the software, and I imagine a lot of people did the same thing. 110
David Flynn @dpfl.bsky.social · 26/11/2024These are lovely. It’s amazing how challenging problems can get with such a simple idea. 000