Provided you do not mind the possibility of losing the offer, I would recommend starting a dialogue with the firm in question. If your issue is partly the starting salary, you may well find there is scope to negotiate this up in today's market. Certainly at the time University offers were made this year the market wasn't as buoyant as it is now and my feeling is that most firms now believe they need more new joiners than they did 6 months back.
The firm in question will undoubtedly not want to lose someone within months of them joining, as this will leave them under-resourced and it will be too late in the day to find a replacement. If you part ways now you will be leaving them with the opportunity to find a replacement before the school year is over. And you may well find that they are prepared to improve their offer to you if you push a little.
From your personal perspective, it is not good news to leave a firm less than 24 months after joining. It just looks bad on your CV and firms you are trying to join will look at this track record of jumping ship and think "what's to say this person will not abandon us in a few months' time too?"
This is obviously your call and you may end up without any job offer if you play your cards wrong - but having a dialogue with the firm will give them the opportunity to both up your current offer and also arrange for you to spend more time with their team to help you assess if they are the right firm to join.<br><br>Best of luck with this decision - and remember that once you've got 2 years of consulting experience on your CV then in a buoyant market it is very easy to move on... Tony