Just to be clear, I agree that some courses are scams, and the people running them do not care at all about the students. Some courses are more scam-y than others. I was mainly rejecting the idea that e.g. certain qualifications are scams because the graduates do not end up getting the relevant job. That is problematic, but the education could still be useful. It might depend on the students’ expectations going in.

If you are only taking a course because you need it to get a job, find out from the people with the jobs what qualifications they want. Do not take the word of the person selling the education!

Then find out if the person offering the job will hire you first, on the promise that you will get the qualification later, maybe part-time. And / or then ask the employer to pay for or contribute to the costs of the course. You’d be surprised how many employers will do this if you show drive / ambition and convince them that your getting the qualification will improve their company / institution. Try not to interpret this as ‘work all the unsociable hours’ – get enough work done in the (standard?) working day.

Hmm… you raise an interesting question, there. Unfortunately, I do not think you will ever avoid the propaganda. If it’s less noticeable because it’s not a random intruder telling you about how stocks work, it’s just more subtle.

But there are strategies for dealing with propaganda and dealing with the bourgeois / liberal world outlook.

1. To be critical you need subject matter to analyse. If you read or watch some Michael Parenti, you’ll notice that he is citing the APUSH-friendly sources. Use your time on your AP sources to learn exactly what claims are being made, and how they are being made. A know-your-enemy kind of thing.
2. If you spend time reading Marxist sources in your own time, you will be well-armed to criticise the APUSH materials. And you will see how Marxists approach similar topics. If you start this work at your age, you’ll be set.
3. It may be useful to keep your head down, practice your best chameleon pose, and blend in. There’s a sense in which you just need to learn the answers that will pass the test. It’s unfortunate and dull, but there it is. Unless we get a revolution soon, it’s these qualifications that will get you a job you enjoy (or don’t hate). Gabriel Rockhill (his video lectures are good, too) said that he only has his job, in which he is able to pay his bills and spend his time doing historical materialism, because he will always be hired as an expert in French Critical Theory (of which he is not a fan).
4. Be an autodidact. Learn more outside the classroom than inside it. Do what’s needed inside the classroom, but study what you really want to study in your own time.