Math teachers serious at improving their craft should find a wealth of resources in the following math education sites:

1. The Klein Project blog is a collection of vignettes written for secondary school mathematics teacher. The blog is unique in the sense that unlike other blogs for teachers, “the vignette is not about pedagogy, but inspires good teaching. It is not about curriculum, but it challenges teachers to reconsider what they teach. It is not a resource for classroom use, but source of inspiration upon which teachers can draw. The goal is to refresh and enrich teachers’ mathematical knowledge.” Each vignette starts with something with which the teacher is familiar and then move towards a greater understanding of the subject through a piece of interesting mathematics. It will ultimately illustrate a key principle of mathematics.

Here is a list of interesting vignettes from the blog:

- Public-key cryptography
- Benford’s law: learning to fraud or to detect frauds?
- What is the way of packing oranges? — Kepler’s conjecture on the packing of spheres
- Matrices and Digital Images
- Fair voting: the quest for gold
- How Google works: Markov chains and eigenvalues

2. The NCETM Portal contains excellent resources and support tools for math teachers continuing professional development.

My personal favorite in the portal is their collection of research study modules. I also highly recommend the Personal Learning section which includes the Professional Learning Framework, Self-evaluation Tools, as well as a Personal Learning Space for anyone registered with the NCETM, which is free. You can use these self-evaluation tools to check your and your understanding of the mathematics you are teaching and to explore ideas on how to develop your practice. Click How confident are you to teach mathematics for sample questions.

3. NRich – is a collection of resources for teachers, students, and parents. It is hosted by the University of Cambridge. I love this site because it promote learning mathematics through problem solving. The following description about their resources in the Teaching Guide page should be enough make you signup to them. It’s free!

At NRICH we believe that:

- Our activities can provoke mathematical thinking.
- Students can learn by exploring, noticing and discussing.
- This can lead to conjecturing, explaining, generalising, convincing and proof.
- In a classroom, the students’ role is to focus on the mathematics while the teacher focusses on the learners.
- The teacher should aim to do for students only what they cannot yet do for themselves.

4. Math Education Podcast is a collection of interviews with mathematics education researchers about their recent studies. This is hosted by Samuel Otten of the University of Missouri. For math education students and researchers, this site is for you.

5. The Math Forum @ Drexel – offers a wealth of problems and puzzles, online mentoring, research, team problem solving, and professional development. The site need no introduction. Their most popular service is Ask Dr. Math.