If your macbook is out of warranty like mine is and you get stuck keys, its actually very easy to pop they keys out (they won't break if you pop it from the correct side, even though they feel well secured).
But this worked for me, try it at your own risk..
Firstly, DO NOT try and pop your key out from the bottom, the bottom part of the key acts as a hinge that will break if you pop it from that direction.
Get something small like a paper clip (I actually used an open stable) to fit inside the gap. Once you slide the paper clip inside the gap, move it to the top of the key and pivot the paper clip forwards (ie away from you) so the top of the key starts to lift. When you have lifted the key enough from the top, pull it with your finger, the key then pops out like a regular keyboard and you can remove any debris quite easily.
Before putting the key back in, have a look underneath the actual key and you will see the "hinges" or hooks towards the bottom of the key on either side. These hinges need to be hooked back in so DO NOT just put the key back in its place and press it down, you will break it! Once you have hooked in the bottom half of the key, you can just press the top of key to push it back into place.
I hope this helps!