Hey guys, I'm applying to schools and I need an academic reference letter. Should I ask the professor in person, or email them? And if I email them should I make the email long and give the reasons why the professor should write me a letter?

If you ask them by email, theyre probably gonna tell you to come and see them in person. So you might as well save some time and see them in person. Unless the prof knows you really really well in that case they could probably write the letter without seeing you but seeing that you wrote that you have to explain to them why they have to write one for you i assume you guys aren't that close

Depends how much of a relationship you have with the prof you're asking.