In no particular order:
Mathematical Association of America (@maanow): Lots of cool math news, stories, and advice. It's also a great way to keep up with the MAA and the work they do to advance mathematics.
Differential Eqns (@diff_eq): If you love differential equations, then you'll love this Twitter feed. Content includes analysis of equations, explanations of various laws, and opinion pieces by the author.
Republic of Math (@republicofmath): Features a wide variety of math topics in different mathematical fields. The Republic of Math loves to participate in #FF (Follow Friday) so maybe you can get a shout out.
Maths History (@mathshistory): Run by the British Society for the History of Mathematics, this Twitter posts bios and facts about mathematicians daily.
Probability Fact (@ProbFact): This Twitter feed tweets one probability fact per day. So if you like probability, then you will probably like it.
Maths Jam (@MathsJam): Maths Jam features tons of cool math puzzles, games, and problems, curated from around the Twitterverse and the web.
American Math Society (@amermathsoc): With lots of tweets about math news, articles, and studies, this Twitter is a great way to keep up to date on the latest math happenings.
Pure Numbers: (@Pure_Numbers): Every day Pure Numbers posts an equation using the numbers in the date. It's a fun way to visualize numbers and can be great for early learners.
NCTM (@NCTM): The National Council of Teachers of Mathematics is the public voice of mathematics education. Their Twitter features great information on the importance of math in education while covering a variety of education debate issues.
Bridges Mathart (@BridgesMathart): This account retweets mathematical art, mathematics that looks like art, and discussions of both, in addition to content direct from the Bridges Organization (for, of course, mathematical art). If you love math and enjoy seeing it represented in beautiful ways, then check this Twitter out.
Wolfram Tweet-A-Program (@Wolframtap): Tweet a 140-or-fewer character program in Wolfram Language to this account, and it'll tweet back with the evaluation of the program. This is a very neat use of technology that can be fun both to interact with and observe, for experienced and new coders alike.
Worldwide Center of Mathematics (@centerofmath): Of course we had to mention our Twitter which features math news, jokes, quotes, and practice problems. We also love to hear from our fans so feel free to tweet us anytime!
Have a Twitter that didn't make the list? Post in the comments some of your favorite Twitter feeds with mathematical content.
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