I think firstly you should make clear why you want to study MBA. MBA is more related with business administration.
If you want to continue the teaching career, then you can apply for other master or doctor degree programes rather than MBA.
In case you want to change your career from teaching to business field, lacks of business experience might be a disavantage, but more important is your potencial in Business administration. While, your advantage in teaching might also be a plus if you can explain that after MBA study, you want to utilize your MBA knowledge in Education industry, say you want to become a manager in some Education or training programme. Your 3years experience of teaching plus MBA will be your unique competency in Education business. |