As we worked on this project as an agency, I had not opportunity to test out some of the assumptions we had. If I had an opportunity, I would definitely do rounds of usability testings with youths. Another thing I notice coming back to this project years later is that some of the visual elements disturb you too much, especially, while reading article about abstract astrophysics. For example, header could have two different states: normal and compact, so that when a user reads and articles, it does not take that much space.
Also I would add more interactivity and connection with OYLA team: more obvious way of get in touch, different tests and trivia, maybe, even propose own content. For instance, for DIY section readers could submit their own tutorials.