For Thursday Techday this week I have been searching for good sites to find virtual manipulatives for base-10 blocks. I'm fortunate that the online site for our math series has great manipulatives. I have a recording sheet I made that I want students to be able to use both with the hands-on manipulatives and the virtual ones that they can access at computer station. We use Go Math, and sometimes we have trouble with the ThinkCentral site so I decided to search out some back-up sites. Hopefully they will help those of you who may not have a site that coordinates with your math series, too. Here are some I found:
National Library of Virtual Manipulatives This is a big library of manipulatives, not just base-10 blocks. To try out the blocks choose "Number and Operations."
Online Learning Center One thing I like about this is the printable base-10 blocks and place value chart. You could send this home with students who don't have internet access.
Learning Box The sound effects would bug me, but I have headphones at all my computers so it would be OK! These are Shockwave and Flash activities, so may not work for some schools.
There are also a few iPad apps that look interesting, but they are not free -- and I try to stay off the slippery slope of paying for apps!