Here is the best stuff that I saw in 2012:
Fawn Nguyen - Her Google Form for reassessments has changed my life for the better. I really like her Foxy Fives problem set. Her love of the Shell Centre materials has sent me digging through their lessons and tasks. This year, her blog became my favorite resource-sharing blog. And she also has a 180 blog? So prolific, and so good. Her work has pushed me to be more organized, and to plan more carefully.
Christopher Danielson - His hexagon investigation might be my favorite post of the year. He's consistently thoughtful and sharp on twitter. Logarithms are another strength of his work. His online course is an exciting experiment. He wrote -- somewhere -- that he constantly asks his education students to make explicit the pedagogical assumptions of a text, lesson or activity, and that line rings in my head nearly daily. It was an excellent year for his blog, and I can't wait for what comes next.
Justin Lanier - I've always enjoyed Justin's work over at I Choose Math, but it's his 180 blog that really opened up his classroom to me. His Geometry class digs into beautiful investigations, and I loved his simplification of the proof that the square root of 2 is irrational. His work shows how exciting class can be when argument, proof and just plain-old thinking are at the center of things. My attempt to emulate his and Paul Salomon's work has been the biggest change in my tone and style this year.
Dan Meyer - Always Dan Meyer. What can be said about his work that hasn't already been said by so many others? A lot of my thinking starts with, "How does Dan pull that off?" His influence is just remarkable, and I get the sense that a lot of people are watching his career very carefully and taking notes.
Paul Salomon - Over the summer Paul shared his introduction to exponent properties with me. Here's a video of him explaining it. (Ignore the goofy redhead.) I walked away from that conversation realizing that I'd been neglecting proof and argument in class, and that it was time to bring them back to the center of our discussions.
Kate Nowak - She's the one that mentioned that she was bringing her CME texts with her to her new gig and got me interested. She's the most creative activity planner out there. Log Wars. Laser Kids. Line of Best Fit. Her work is just so impossibly and consistently good.
Finally, not really a blogger, but whatever:
CME Project - I bought the teacher's editions over the summer, and their work is just phenomenal. Owning these texts has raised my baseline performance by giving me high-quality material to lean on. The texts have also shown me how to teach so that proof and structure become visible and integral.