How can I schedule a date?

So I’m really into this girl, and I know she’s really into me. We met through a friend and we talk a lot on msn and Twitter, and during school we saw each other a lot too. Now, it’s summer and she lives like an hour drive away. Her mom is kinda strict and likes her to be home early and she works a lot during the day, also on weekends. We’ve been communicating a lot over the internet because that’s our only way (she doesn’t have a cell phone), and I really want to see her again, but as a date. I’ve asked her out over msn (yeah, I know, kinda sucks but it’s the only way possible), and she says she really wants to but she can’t because of timing and her mom’s strictness.

Do you have any tips on what I can do?