If you are a full-time student for most of the year, you may find you won't need to file a return if you work just two or three months of summer. However, if you’re eligible to receive a refund of any taxes withheld from your paychecks, you will want to file anyway to get that money back.
The ordinary filing thresholds do not apply to you if you’re still claimed as a dependent on your parents’ tax return. In this case, you will need to file a tax return if your total earnings are greater than the standard deduction available to single filers (without any increase for a personal exemption). These dependent filing rules only apply to your earned income. You will also need to file if you received unearned income in excess of $950, regardless of any other earnings. Unearned income covers non-employment income such as interest and dividends.