My answer on Avvo:
Yes, you can be written up, denied promotion and denied education expenses while on intermittent FMLA leave. The question is: will doing so violate the FMLA? Possibly. An employer is allowed to discipline an employee up to and including termination while they are on FMLA leave as long as the FMLA leave itself is not the motivation. So, these things would be lawful if they happened, for example, because you were absent for other, non-FMLA reasons or because you ran out of FMLA leave.
If you believe the employer did not give you all the FMLA leave you were entitled to or it did these things in retaliation for using FMLA you should consult with an experienced employment attorney. Keep in mind that the FMLA has a 2 year statue of limitations.