Wow! How rude! I agree with the ladies above...the first thing I thought when reading your post was that they are not coming back and do not plan to pay you. Was there any kind of problem before this either with the parents or with the child? Something that could give you a clue as to why they might want to leave? I also agree with the others...do not go to their home. Just send them an email letting them know that whether or not their child returns, they still owe you the money (I am assuming you have a notice period which must be given) as per your contract and then quote the section of your contract that deals with this. I would also tell them that failure to bring the money today will be taken as their notice and you will start advertising the space. Good luck!