How to fold paper plane which can really fly?

Paper ariplane probably is the most easy toy to make. No matter you're boys or girls, I believe that most of you have ever made and played with paper airplanes when we were kids. But do you know that there are many models of paper airplanes which can really fly? 
The videos below will show you some different ways to make a paper airplane. Let's show your kids and help them to make it

This model is actually not an airplane but it can fly so I just put it here in case you're interested in it

This one is a bit compliated, but it worth it