If you have an employment contract, its terms may be enforced; so to the degree that it guarantees your job or prevents you from being terminated, the contract would protect you.However, without an employment agreement, you are an employee at will. An employee at will may be terminated at will--at any time, for any reason. Also, employers may change the job requirements for employees at will at any time. Therefore, it would seem that your employer has a right to do this: they may now require a bachelors, and terminate you if you don't have one.The exception would be if you could show that the real reason for this change is to discriminate against you due to your race, sex, religion, age over 40, or disability status. (That's under federal, or national, law; some states may add additional protected categories, such as sexual orientation.)