http://nlvm.usu.edu/en/nav/vlibrary.html National Library of Virtual Manipulatives

 http://illuminations.nctm.org National Council Teacher Mathematics (NCTM) Illuminations Illuminations is designed to Provide Standards-based resources that improve the teaching and learning of mathematics for all students. 
 Provide materials that illuminate the vision for school mathematics set forth in Principles and Standards for School Mathematics. Illuminations is part of the prestigious Verizon Thinkfinity program.

https://www.sascurriculumpathways.com/portal/  SAS Currciulum Pathways   Interactive, standards base resorces in the core disciplines We develop interactive resources that utilize technology to create learning environments otherwise difficult to achieve in the classroom setting. Our resources are intended to supplement instruction to engage students in meaningful learning experiences that foster a deep, robust understanding of concepts.

http://onlinestatbook.com/rvls/index.html Statistical Analysis Manipulatives from Rice Virtual Labs

http://highered.mcgraw-hill.com/sites/0073022845/student_view0/virtual_manipulative_kit.html Virtual Manipulatives Kit  This updated Virtual Manipulative Kit  can be conveniently accessed and moved about the screen.
 Each of the nine manipulatives has a work area with toolbar to display manipulatives and a notepad for recording data and results. Both the notepad and the work areas can be printed to turn in for assignments or projects