Activity
Mon
Wed
Fri
Sun
Jul
Aug
Sep
Oct
Nov
Dec
Jan
Feb
Mar
Apr
May
What is this?
Less
More

Owned by Robert

The Science of Math

159 members • Free

Learning math by doing

Ruby on Rails Wizardry

46 members • Free

For Ruby on Rails enthusiasts. Learn from a 40+ year senior developer, 15+ years in Rails. Join to master Rails, share tips, and innovate!

Memberships

Flippin’ Math Culture Club

121 members • Free

Skoolers

182.3k members • Free

3 contributions to Flippin’ Math Culture Club
Two negatives make a positive.
Often, I hear exactly that… “well, two negatives make a positive….”, the students say. Sometimes they’re right. And sometimes, they’re wrong. Can you follow my vague, barely-told story and fill in the details? When would they be right? When would they be wrong?
1 like • 5d
A negative is one half turn and is applied by multiplying whatever you have it next to by the half turn. If a value is negative, it's heading the opposite direction of positive. multiplying by another negative turns you half way around a second time, and points you back at positive. this is the "a negative times a negative is a positive" If you are wondering if negative is really rotation, ask Euler, it's his Identity. On the other hand, if you are adding two negative numbers, that's just moving in the negative direction both times.. which makes it more negative. This is way easier to understand if the student experiences it first. Turning around and Walking it out is my favorite tools for this.
Who here tells the story of x?
How many of you guys train your students to “tell the story of x?” Once when I was substitute teaching as a coteacher in a middle school math class, the teacher revealed a strategy… and I’ve used it ever since. Instead of just “solving an equation,” they framed it like this: “X was sitting there minding its own business…. Until things happened to it. “Why isn’t x by itself?” It gets multiplied. Stuff gets added to it. Sometimes it gets trapped inside parentheses like a tiny hostage 😅 And your job? * Figure out everything that happened to x… - then undo it step by step to get back to the original value. It turns math into less of a “what do I do???” and more of a: “what happened here…?… and how do we get back?” And honestly… students get it so much faster this way. I’m curious— Do you teach like this? Would this have helped you when you were learning? Or if you’ve never heard it framed this way, what’s your reaction? Lemme know if you want to see this strategy in action! Drop your thoughts 👇
1 like • Apr 15
I start introducing algebra by using a physical two pan balance, where the balance itself provides the feedback for what's equal. I then have a cup that I have the student name, and then label with a single letter abbreviation for the name. Then I put an unknown number of cubes in the cup, and a few cubes next to the cup on one side of the scale. I have the student balance the scale, then write down what they see including the units (abreviated as c for cube). g + 3c = 7c This gets them used to using letters in their math for both the units and the unknowns. I then continue the process of having them "solve" the problem using written observation and the scientific process. I find this gives them an intuitive understanding of units and unknowns as simply abbreviated names for things.
Got a favorite mathematician?
Two of my roosters are named after two of my favorite mathematicians. Pascal and Benoit! (That’s Pascal in this pic!) Anyone else got favorites?
Got a favorite mathematician?
1 like • Apr 11
Definitely Leonhard Euler. Him and Galileo Galilei. And Archimedes, can't forget about him.
1-3 of 3
Robert Ferney
1
2points to level up
@robert-ferney-7215
Flipper of bits, Maker of things

Active 3h ago
Joined Sep 28, 2025