There is no exemption from tax for full-time students. Every U.S. citizen or resident must file a U.S. income tax return if certain income levels are reached. Factors that determine whether you are required to file an income tax return include:

If your income is below the filing requirement for your age, filing status, and dependency status, you will not owe income tax on the income and will not have to file a tax return. You may choose to file if you have income tax withholding that you would like refunded to you. For more information on filing requirements refer to Publication 501, Exemptions, Standard Deduction and Filing Information.

You may have given your employer a Form W-4 (PDF), Employee's Withholding Allowance Certificate, claiming exemption from withholding. To claim exemption from withholding, you generally would have to have had no tax liability the previous year and expect none in the current year. An exemption certificate is good for the calendar year.

For related topics see Tax Information for Students.

Generally, if an employer does not withhold income taxes, social security, and Medicare from your pay, you are being treated as an independent contractor (self-employed person).  Verify with your employer if they consider you an employee or an independent contractor.

If you believe an employee relationship exists and you cannot resolve this matter with your employer, you should submit a Form SS-8 (PDF), Determination of Employee Work Status for Purposes of Federal Employment Taxes and Income Tax Withholding. The factors used to determine if an employer-employee relationship exists are covered in Chapter 2 of Publication 15-A (PDF), Employer's Supplemental Tax Guide.

If your status as an employee is not at issue, it may be that you are in a category of employment whose earnings are not wages for federal employment tax purposes. Find out from your employer the reason that social security and Medicare taxes and income taxes are not being withheld from your pay. If you have further questions, contact the IRS toll-free at 800-829-1040 or visit an IRS walk-in office for assistance.