The site is nice, clean and (seemingly -- I don't know the local environment at all) informative. SEO features are adequate already; only external factors (quality inbound links, social media marketing, etc.) can really make a difference at this point.
As for monetizing, you'll need to be very careful. Your main advertisers, whether you use something like Google AdSense or you do your own advertising sales, are going to be outfits like test prep services, and you'll want to make good and certain that your site doesn't become a sort of a front for cheats and scams without seeming to be a "friendly front door" for any single company (which may operate under several different names/URLs for marketing reasons). The quickest ways to be labelled a nuisance site is to either play host to other nuisances or to look like a front for something else. And since your site has a built-in time limit for utility for any one user, a subscription or "freemium" content model won't work, so adverts will be your best bet. As long as you're careful and willing to block ads from, um, questionable companies (that will require research on your part), you may very well find that the click-through rate on a site like yours will be much higher than average.