Can you get wireless highspeed internet through Alltel if you buy/have a pay as you go phone or plan?

Our son is getting older and more into sports and it would probably benefit us if he has a cell phone. In our thinking, because we live in one of those places that you can only get dial-up internet service (believe me, I have tried calling every internet service) we should get him an Alltel cell phone and so we can use Alltel's wireless internet through his cell phone and it would benefit all of us....so we can get rid of our dial up. What we were thinking is getting a prepaid Alltel plan because we want our son to only use the phone to call us and in the evenings and weekends, we can all use it to connect to the internet. Can you do this with a prepaid Alltel plan/phone?