Those phone calls with your mom are getting kind of awkward as you're getting further along into the year and doing more and more things she would never approve of. In order to dodge some of these bullets let me explain what you should say, as well as what it will actually mean.

What you say :: What you mean
I kind of have a girlfriend
I hook up with the chubby roommate of the girl I'm interested in
I don't get a lot of homework
I haven't been to class
We haven't gotten our first test back
I failed the first three tests
It was an open book exam
I cheated
I'm pretty popular with the ladies
I masturbate a lot
I'm making some great friends
My roommate tea-bagged me last night and sent the picture to
How's grandma?
I'm worried that I jinxed grandma's life by telling my professors she died so I could get out of class
Books are expensive, and my meal plan isn't any good
Send me beer money
Can I talk to Dad?
Something is wrong with my dick.
I might come home next weekend
I'm going to try to get a handjob from a high school girl while you do my laundry
I should get back to studying
I need to go whack it
Can you hold on for 20 seconds?
I need to whack it
The dining hall has a waffle bar
I'm getting fat
Can you send me some of my video games?
No one here likes me
My roommate is alright
My roommate jerks off whenever he thinks I'm asleep
Can you send some fabric softener
I'm gay