"Common Core is driving a lot of the growth in open education production and curation, with new databases and sources popping up left and right. It can be overwhelming to wade through everything, and find a source that works for your classroom. With that in mind, here are some math open education resources for elementary educators."
ArXiv is an e-print service in the fields of physics, mathematics, non-linear science, computer science, and quantitative biology that is owned, operated and funded by Cornell University. ArXiv is also partially funded by the National Science Foundation.
Off-Campus Access: Available to all users.
"DASL (pronounced "dazzle") is an online library of datafiles and stories that illustrate the use of basic statistics methods. We hope to provide data from a wide variety of topics so that statistics teachers can find real-world examples that will be interesting to their students."
"Contains online journals, article collections, monographs, and other electronic resources in the field of mathematics."
A valuable set of math reference tables in English (y en Español).
Consists of: Math in the News, Convergence, MAA Reviews, Classroom Capsules and Notes, Course Communities, Loci and JOMA, and Mathematical Communication.
From Penn State University - a comprehensive set of links to math sites around the world, includes a search engine.
A comprehensive directory of math resources, with a strong emphasis on teaching. An annotated catalog of mathematics and mathematics education web sites.
An introductory course on teaching and learning science and mathematics in a variety of K-12 settings. Topics include education and media, education reform, the history of education, simulations, games, and the digital divide.
Resources associated with the course are also available.
Online handbook of mathematical functions developed by the National Institute of Standards and Technology.
A cross-index and virtual repository of mathematical and statistical software components of use in computational science and engineering.
A web resource of math review material covering Algebra, Trigonometry, Calculus, Differential Equations, Complex Variables, Matrix Algebra & Mathematical Tables.
An encyclopedic website containing definitions and discussions of every aspect of mathematics.
A listing of 16 famous unsolved problems in math.
A web-based computational knowledge engine of facts & figures of "math & more". Includes information for educators.