http://www.brightstorm.com/science/ - Has multiple science textbooks used by lathrop and multiple videos connected to said textbooks. Includes math help in multiple stages. Includes english help in writing, liturature, and grammer. Has prep for tests like the SAT ACT and AP classes.
http://www.wolframalpha.com/ - Useful for homework help in all scenarios.
http://ww2.kahnacademy.org/ - Has videos of how to do any math from Algebra 1 to Calculus.
http://www.bibme.org/ - A great Bibliography tool with muliple formats.