There are a lot of apps in Facebook that does weight the friendships and generated images. Maybe one of them have their algorithm opened and you may use it to improve the accuracy.
I'll rephrase that: adding a weight to an edge is not hard, I actually having several heuristics on hand to do that. It's just really time consuming the first time you do it, because you have to load a lot of data in order to be accurate. Moreover it requires additional permissions, which I'd rather avoid.
My biggest problem was not really with Evernote but with create discipline to take important notes. The only version I tried to use was the Android version, and I couldn't create value using it.
I would teatch them to learn from different cultures, I think it was a waste of time destroy everything they found in each civilization they conquered like Incas, Mayans and other civilizations in europe. Probably there were a lot a writing documents that would be very useful to our society today.