I grossed about $900 this year, I have 2 kids 15 & 9

No need to file a tax return at your income level, unless you are claimed as a dependent of someone else, in which case you may have to file if a portion of the $900 is unearned income. However, even if you are not required to file you may want to if you have had some income tax withheld from your wages that you want to get back, or if you qualify for the Earned Income Credit.