See https://www.irs.gov/taxtopics/tc513
Note, in particular, that if you are not self-employed (i.e., you are an employee), you cannot currently deduct the cost of work-related education expenses due to tax reform (the TCJA).
Further note the other requirements:
(1) The education must maintain or improve skills needed in your present work, or
(2) A law requires the education in order to keep your present salary, status or job
(3) The education must not be part of a program that qualifies you for a new trade or business.
