The problem often isn't learning itself, but rather that you go through the material without ever really checking whether you've actually understood it. The previous tip about active exercises is good, but I'd take it further: try spending a week where right after learning, you explain what you just learned without cheat sheets or solutions - write it down, tell someone, whatever works. That'll show you immediately where the gaps are. With math and English specifically, it could also be that you don't have the basics down cold, and then everything after that becomes a struggle - maybe it's worth taking a step back and really cementing the fundamentals instead of always pushing forward.