Answer varies, but possible answers include: The money you spend to go to Disneyworld can be used for shopping, saving for future emergency cases, saving for buying a new car,... The time you go on a vacation can be used for doing homeworks, learning a new sports or hobbies and you can even to do part-time jobs to earn more money.
Work Step by Step
You can consider any circumstances when you face trade-offs between the cost of going on a vacation to Disneyworld with other things. It can be the monetary cost which means you can use the money for different purposes instead of spending for the vacation. It can also be the time cost of it. With that time you can accomplish you school's project, do part-time job to earn more money.