Vacation leave - Full-time employees receive between 13 and 29 days per year, depending on length of service. Part-time employees receive vacation leave based on hours worked. receive sick leave based on hours worked.
Talk to HR and ask for a copy of the tuition reimbursement policy. It's possible it says this is up to your manager and that HR will tell you it's up to your manager. But they might not, they might say you should be reimbursed regardless of your manager's feelings on the matter.
Under current Minnesota law, employers are only entitled to either monitor their employee's calls, read their emails or search their desks if they advise them of their rights to do so in advance. Additionally, they're only allowed to do so for a business-related reason.