If you know anyone struggling with their algebra, chemistry or many other subjects, offer them to check out Khan Academy.
It has lessons on: algebra, chemistry, biology, calculus, CST, economics, finance, linear algebra, statistics, probability, trigonometry and many others.
Khan Academy was chosen to be one of top 5 ideas chosen by Google to receive 2 million $ in funding as one of the most promising free education technologies.
Check it out at:
They also have an iPhone/iPod app for it as well, read more about it here:
Khan App
http://lifehacker.com/5724572/khanapp-offers-free-education-to-go
