A school with a faculty that has expertise in that field -- published authors, researchers in that field, etc.
A comprehensive curriculum that provides content on both academic teaching (in colleges, etc.) and also in nursing professional development. You never know what type of education you might want to do in the future. They should also teach about clinical education, classroom education, online education, etc. The best programs cover all types of nursing education.
A school that will help you find practicum preceptors and facilities.
A school that is academically rigorous -- and provides a good foundation in all types of scholarship
and research. It should also set you up well to enter a PhD program should you decide to do that. If you join a university faculty, you may be expected to get a PhD and you will want to be prepared for that. Even if you don't decide to get a PhD, your job performance evaluation may include scholarly activity and you'll want to be prepared for that.
Those are just a few thoughts off the top of my head.