First Week: Which One Doesn't Belong?

Hello Mayfield Families!

I hope everyone had a great first week of school. I LOVED being back on campus with the students. Students, if I haven't seen you yet, come by the learning center to say hi! Parents and guardians, I'd love to hear from you too: email, call, or set up a meeting to talk about anything MATH!

Our Problem of the Week launched on Friday, and it was so joyful. This week's problem was a "Which One Doesn't Belong?" with these four numbers: 9, 16, 25, 43. Students and teachers came up with reasons I hadn't thought of. Some went deep with the math, some got a little silly and creative. That's exactly why I like these activities. They open the thinking up to everyone. And eventually a student who says "I pick this one because it looks weird" starts saying "25 is the only number divisible by 5." 😉

It got me thinking about why certain numbers appeal to us more than others. Tiago said 16 didn't belong because it has the most factors. That's why I love the number 16!  I loved turning 32, because 32 = 2⁵ — the only perfect fifth power besides 1 that I will ever be! (And then I start thinking about how exponential growth compares to linear growth... I can't help it.) 32 is also great because, like 16, it has a lot of factors — including 16 itself.

So here's something to think about at home: What's a fun age to turn? My niece loves being 11 because both digits are the same. 10 is fun because it's the first two-digit number.

Dani said 43 didn't belong because it's the only prime, and some people LOVE prime numbers. Our graduating class of 2027 will graduate in a prime-numbered year! The last one was 2017.

Others looked hard for patterns. Mrs. Seymour noticed that the digits of three of the numbers add up to 7 (16, 25, and 43) — and only 9 doesn't. Abby noticed that 25 is the only number whose ones digit isn't divisible by 3.

And then there were the silly ones. A little shameless flattery from Catherine: "25, because Mrs. Reeser doesn't look 43 — but she doesn't look 16 or 9 either." I was delighted.

I'll post these "problems of the day" on the wall in the learning center as often as I can, and you can submit answers online too. Next week's puzzle is up now — take a look!

One last thought, carried over from my previous update because it bears repeating: I didn't always think of myself as a math person, and I meet a lot of students and parents who feel the same way. If that's you, I'd say the story isn't finished. Math isn't a race to the right answer; it's a way of thinking. Just like this problem: it's not about the answer, it's about the how you think of the numbers. My commitment this year is to help every student at Mayfield find some real joy in math.

Brittany Reeser

K–8 Math Specialist and Math Department Chair