I experience this myself and its really a lot fun than studying through books. Maybe some of you would prefer reading through paper instead of screen, I understand because sometimes reading through screen is really hurting your eyes. However, that doesn't really matter, nowadays, all computers are come with a LCD screen which reduces many problems.

Back to e-learning. In order to learn effectively through internet, you must have the right resources or you will be learning something incorrect.
You do not need a very good search engine to search for good resources or references. All I use and only use is "Google". But you must know some basic so that you can search as accurate as possible.

For example:
I want to search for "SPM Mathematics". You should type ""SPM+Mathematics"" instead of straight away type "SPM Mathematics". Trust me, it does make a difference.

I have some useful links for certain subjects:
Chemistry: Structure of Atom
Mathematics and Additional Mathematics
Many animations regarding Biology