I think this is a really good price; you're lucky to get two games for that elsewhere!
On presentation of Valid Student ID (be it UCAS card or University admissions card, or something similar), you can get unlimited bowling for £6.50!
"Love to bowl? With Tenpin you can have unlimited bowling!! That means you can bowl for as long as you like within the timeframe allowed. To check the availability, times and prices for your local site, please call our sales team on 0871.... Unlimited bowling is subject to lane availability and you may be requested to move lanes after your first 3 consecutive games during busy periods."
As far as I can tell, you can turn up at 1pm and just keep bowling until 5pm!
EDIT: Sunday-Thursday only! Sorry, forgot to put that part in.