Is 250mb of data good on an iphone?

I'm currently researching my contract I'd like to get when I upgrade (I'm 13, and I'm hoping to get my first iphone, eeek!) I was thinking, is 250mb good on an iPhone 4S with 16gb? What would it let me do? What would it not let me do? What is the different between the 16gb and 250mb? Is it ok for a 13 year old who doesn't have facebook(deactivated it-BORING)and is addicted to twitter.

Depends on that 250MB data service plan is monthly or yearly?
I used 100MB data service plan per month and its more than enough for iMessaging, emails, twitter, Path, instagram and some games.

The 16gb is the storage the phone has for music, movies, pics, and apps.

the 250mb is the ammount of data you use in a month. This is practically NOTHING. A couple of time waster games downloaded over your cellular network would eat through that. Some of the larger games come in at 1gb (1000mb)
if you are on Wi-Fi most of the time, you may be OK, but as soon as you step outside of that Wi-Fi zone, you are eating away at that data… Then you get a charge for every gb of data you go over leaving your parents with a HUGE bill.

if you only use the phone at home connected to your home Wi-Fi, then turn off mobile data, you will be ok, but doing twitter and web browsing ect, won't happen unless you are on Wi-Fi.

Data plans vary for many reasons and it honestly depends on what you are going to be using our data for. I have 3 gigs a month on my iPhone 5 and it hasn't failed me since. 3 gigs is enough to be safe and if you need to do high data things, you won't have to worry about going over too much. 250mb of data is very risky and it will get you in trouble unless you are only doing things like checking your mail. But seriously, you don't need an iPhone at your age unless you get a job and earn it with your own money like I have… Get an iPod 5 instead.