Which Android tablet do you have? (Device model, manufacturer, etc.) You may be able to hard-reset the device if you remember your Google Account details. (assuming you have a google account on the tablet, that is.) :How to unlock an Android phone/tablet - PC Advisor
It's no help if the OP doesn't provide enough info, as "jelly bean tablet" can refer to the thousands of android tablets out there equipped with Jelly Bean.