What's a synonym for “Bull**it” when referring to something like writing English papers? [duplicate]

Solution 1:

This isn't a course where you can just wing it. You have to be fully prepared; you can't wing it/ fly by the seat of your pants, you can't make it up on the fly/ or perhaps "you can't make it up as you go."

Solution 2:

I want to use a more formal synonym and something less explicit/slang-like.

I think this is the key to your question which, in other readings, is more likely to just provide synonymous slang terms.

"It’s not an easy class where you can just bullshit your way through it.”

So, you want this rephrased in a more intellectual or academic sense.

Try:

"It's not an easy class where you can get away with making unsubstantiated claims."

Merriam-Webster provides this definition of unsubstantiated:

: not proven to be true : not substantiated · an unsubstantiated rumor/report · a plausible but unsubstantiated theory

[In contrast to substantiated.]

1 : to give substance or form to : embody
2 : to establish by proof or competent evidence : verify · substantiate a charge

It also provides this definition of claim:

1 : a demand for something due or believed to be due · an insurance claim

She makes the claim that sea levels will actually go down.
He made false claims about his past job experience.