Children who work only part-time or just during the summer may have too much money withheld from their paychecks, because most employers base withholding on a worker's annual pay, says Price Waterhouse, the accounting firm. If children pay too much withholding, they must wait to file a tax return to get a refund of the excess. Children can get around this problem by asking that the employer use the part-year method of withholding. To do this, submit a written request to the employer that says the child expects to work less than 245 days during the year, a period that includes weekends, vacations and sick days. The clock starts running the first day of work and stops on the last, Price Waterhouse says. If the child had another job earlier in the year, the date of the last day on the job must be included in the request.