How bout this: You have an A minor scale if you flat the B its Phrygian. Think about it starting on different scale degrees only when you need to memorize it or something. At least that's how I did it in school, but then when I went to write music I'd think about changing the key signature. Or you could think about it as half and whole step patterns. Sorry I don't have a website to give and I am currently too lazy to explain every mode.
