One of the best ways to save for a laptop computer or any other large purchase like that is to make a savings plan for yourself. Make yourself put away about 1/2 of your allowance or other money from gifts/work. Put this money into a savings account so that you won't be able to touch it. Ask your parents if they would be willing to help you save along the way, by matching your deposits into your savings account. Also, try and consider cutting down on unneeded purchases if you can. You can possibly get a laptop computer in less than 1/2 a year if you put in $15 a week and your parents match that!
Money Smart Kid