He pledged to give some money in charity and he does not have that money now
Question

                I am a student and only 16 years old. I had attended a lecture during the summer of 2008, where at the end they presented a sideshow of some of the poor Muslim countries. Me and my friend got emotional, so together we pledged to donate a large sum of money. Neither of us have a job, or money of our own. We are doing little things to raise the money, but so far after working very hard we only raised a third of the sum. In June, I will be moving to a different country InshAllah, and until then I will try my best to raise the money. However, if I leave the country before I have donated the total amount I have pledged for, will I be in debt?.
Praise be to Allah.
    Firstly: 

    We appreciate your concern for the Muslims' affairs and your 
    eagerness to find out about their situation and help them. This indicates 
    that Allaah has blessed you and your friend with faith and sincere 
    brotherhood. We ask Allaah to bless you both and help you to obey and please 
    Him. The Prophet (blessings and peace of Allaah be upon him) said: “The 
    likeness of the believers in their mutual love, mercy and compassion is that 
    of the body; when one part of it is in pain, the rest of the body joins it 
    in restlessness and fever.”

    Narrated by al-Bukhaari (6011) and Muslim (2586). 

    And he (blessings and peace of Allaah be upon him) said: “No 
    one of you truly believes until he loves for his brother what he loves for 
    himself.” Narrated by al-Bukhaari (13) and Muslim (45). 

    Secondly: 

    If a person makes a pledge or a vow to do an act of 
    obedience, then it is obligatory for him to fulfil it, because the Prophet 
    (blessings and peace of Allaah be upon him) said: “Whoever vows to do an act 
    of obedience to Allaah, let him go ahead with it, and whoever vows to 
    disobey Him, let him not disobey Him.” Narrated by al-Bukhaari (6202). 

    A pledge to give charity is a kind of vow to do an act of 
    obedience that must be fulfilled. If you are unable to fulfil it, then it 
    remains a debt that you owe until you are able to do it, and the fact that 
    you are travelling does not change that. 

    The scholars of the Standing Committee for Issuing Fatwas 
    were asked: I made a vow that if I got a job I would give 600 riyals to 
    sponsor an orphan on behalf of my father and mother every month. After that, 
    I sponsored one orphan for a year and a half, at a cost of 2400 per year, 
    then I stopped because of my financial situation. Now, after I stopped, I 
    was determined to sponsor an orphan again on the basis of the accumulated 
    amount and I found it is 25,000 riyals. 

    My question is: What do I have to do? 

    They replied: You have to fulfil your vow, because it was a 
    vow to do an act of obedience and the Prophet (blessings and peace of Allaah 
    be upon him) said: “Whoever makes a vow to obey Allaah, let him go ahead 
    with it.” And you have to make up that amount for the months during which 
    you did not pay anything, because it became a duty on you as a result of the 
    vow. May Allaah accept it from you and compensate you with that which is 
    greater and more beneficial. Allaah says (interpretation of the meaning):
    “and whatsoever you spend of anything (in Allaah’s 
    Cause), He will replace it. And He is the Best of providers” [Saba’ 34:39]. 

    We advise you not to make vows in the future, because the 
    Prophet (blessings and peace of Allaah be upon him) said: “Do not make vows, 
    for vows do not change qadar (the divine decree) in the slightest, but they 
    make the stingy person give something up.” Saheeh – agreed upon. End quote 
    from Fataawa al-Lajnah al-Daa’imah, 23/342. 

    We ask Allaah to guide and help you both. 

    And Allaah knows best.