Mystery Science is a great resource for 2nd - 5th grades. They're offering a free year subscription for a limited time.You should sign up quickly, while it's still free (it normally costs $99 per year). I just signed up and requested my teachers to.
http://mysteryscience.com/
Great article on Twitter in education on edcircuit.com by John Padula. "If I told you there was a global network of passionate educators available to converse with you - on any subject and at any time - would you be interested? What if I told you this amazing worldwide network was also free? Would that peak your interest?"
Direct link to sign up for online learning site that is usually premium. Great for PreK through at least first grade. Students earn tickets to dress characters, decorate a house, and get pets with reading and math content.
An easy way to create a form to have teachers, parents, and others sign up for open time slots. It will capture email address, phone, street address as you choose and one additional text entry of your choice for free.