If you want serious help, you have to seriously co-operate and try to understand. I cannot beam skill to you, so if it is beyond your ability to do what I say without me looking over your shoulder... then you are a consumer who should buy another one, as it is far cheaper than me coming over there to watch. If nothing else, print what I put and take it to your teacher and see what they think, or at least be thankful these devices aren't around $200, so the loss isn't as bad as it could have been.
I am still wondering, which part did break off - the part of the tang towards the battery or the part towards the circuit board. Without some sort of clue as to what (exactly) you had to fix, I have no idea how extensive any side damages could be... which makes pretty much any help I or anyone else could give you through text messages "peeing into the wind", so to speak (in laymans terms).
Any words you don't understand, Google will be happy to help put them into context. Just try this for example, on Google: "wiki SRAM" or "wiki PCB"
Sorry if what I am saying isn't a tonne of help. I learned with little to no instruction, and I have always been a firm believer, that "if I can do it, anyone can."
Or others 
