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# Category Archives: teaching

## Introduction to Mathematical Thinking with Keith Devlin

I just learned from Denise at Let’s Play Math! that Keith Devlin is going to be teaching a course on Coursera called Introduction to Mathematical Thinking. It’s free and open to anyone with only a background in high school math. … Continue reading

Posted in links, teaching
Tagged Coursera, free, Keith Devlin, mathematical thinking, online
1 Comment

## Penn Alexander math club: map coloring

Today in math club I had the students explore map coloring. I tried to leave it as open-ended as possible to start—I just said that we were going to draw maps with countries, and try to give each country a … Continue reading

Posted in geometry, pattern, puzzles, teaching
Tagged four-color theorem, graphs, map coloring, math club
4 Comments

## MangaHigh.com

I recently received an email suggesting that I check out the website MangaHigh.com, which has interactive math-based games for elementary through high school students. Now, I am generally pretty skeptical of such things. For one, they are usually of relatively … Continue reading

## The haybaler

At Penn Alexander’s math club yesterday, the students worked on a fun puzzle that I’d never seen before. It goes like this: You have five bales of hay. For some reason, instead of being weighed individually, they were weighed in … Continue reading

## Who Am I?

An excellent puzzle from JD2718: There are five true and five false statements about the secret number. Each pair of statements contains one true and one false statement. Find the trues, find the falses, and find the number. 1a. I … Continue reading

Posted in challenges, logic, number theory, puzzles, teaching
Tagged number, puzzle, secret
13 Comments

## Number bracelets

Recently I’ve been volunteering with the middle school math club at Penn Alexander, a PreK-8 school in my neighborhood. Today we did (among other things) a fun activity I’d never seen before, called “number bracelets”. The students seemed to enjoy … Continue reading

Posted in arithmetic, iteration, pattern, sequences, teaching
Tagged activity, bracelets, number, Penn Alexander
12 Comments