Question

Answer

Yes it is. Just remember that you are given vacation days during the year which you can use in this situation. If your contract stipulates otherwise it is not possible; 5 days during winter and 5 days during summer vacation. Be sure that this does not apply to you before booking your flight. You should also consider that most public schools will not be able to accomodate the wedding if it is during the school year. But in either case, you should consult your head teacher/director/boss well in advance so you and/or your school time to make arrangements.
I hope this helps.