Can I use a iPhone for creative photography?

I'm taking a creative photography class in virtual school. Would they ever know I'm using a phone when they said I can't?

Yes… The EXIF info for starters would rat you out and then there are other obvious tell tale signs than a tiny sensor was used (file size for example).

IF they look at the data in the image file (exif data) it will show. You can use a program to strip exif data, but i'm guessing they'd want you to leave it intact so they can look at the settings you used. Just buy a cheap digital camera or a used film camera.