How can I make 4,000 dollars in 5 months? I'm 15 going on 16?

Hi I'm 15 and I'm am going to be 16 in October. I need help. My family and I are moving and money is VERY tight. But there's a trip to Ireland, Scotland and London I want to go to but it's $3,200. I really wanna go but I feel like its not going to happen. I've always wanted to travel and I think this is my last chance to ever leave the states. Can anyone help me do a fundraising thing or maybe jobs I can do to make the money? I need it very soon! I just don't want to miss my one and only opportunity.

1. Learn java and/or Objective C and program apps and/or games for android and iphone.
It only takes $25 to be able to post a game on the android market, I think for iphones it's more expensive, more like $100. But you can make some good money off of apps, just look it up online for more details. It's kinda hard to learn programming though, but it depends how motivated you are! Plenty of people learn it on their own as teens.
2. You could get a job. A lot of states allow a limited number of hours to 15 year olds. Google your states underage labor laws.
3. You could do your regular fair share of babysitting, lawn mowing, dog walking. Look for gigs on craigslist. If you go to craigslist and click on gigs at the bottom.
4. Maybe sell some things on craigslist as well? Like, if you have old computers or phones, you might make a bit of cash. You can't really sell on ebay cuz you have to be 18, but on craigslist no one really knows your age, they just bring you cash and you bring them the item, but make sure to meet up at a public place, for safety.

Your last chance? You are only 15. I suggest you stay home. Go when you are an adult. You will enjoy and appreciate it much more, and it is easier to get around and do things.