Robert Kaplinsky's Problem-based Search Engine
youcubed.org is the brainchild of professor Jo Boaler at Stanford University. Jo and her students in the mathematics education program at Stanford have put together an amazing site with lots of incredible tasks that support growth mindset in mathematics. There is so much here to investigate! Check out the Week of Inspirational Math (week 2 now includes lessons for K-2 students), the online courses for students, teachers, and parents, and lots of rich tasks and research articles.
Middle school teacher fawn Nguyen has created a site with number talks and pattern talks. Here are her tips for how to use them. Great for building an understanding of algebraic functions.
Number Talk Images is a French website full of dot card and photos of unique object arrays. It's nice to see that the number talk movement is international. There is a great resource page and a link to student work as well.
Conceptua provides interactive, visual tools are ideal for teacher-facilitated, whole-class instruction, "Number Talks" and for parents supporting their students at home.
Splat was created by Steve Wyborney as a fun tool to build number sense. Lessons are ready-to-go powerpoint presentations that cover and reveal dot images. Great for subitizing, addition, and stubtraction.
Illustrative Mathematics is a fantastic resource for tasks that explicitly illustrate each grade level mathematics standard. Great for use as warm-ups or exit tickets.
nzmaths is a fantastic resource for rich, open tasks K-5. Useful for centers! (credit Julie McGuire)
Inside Mathematics features classroom examples of innovative teaching methods and insights into student learning, tools for mathematics instruction, and video tours of the ideas and materials on site. Your Problem of the Month can be found here!