The best way for me to describe how a teacher needs to behave when it comes bettering themselves, would be to compare it to a horse with blinders. I think when someone has been teaching for a long time, they will get stuck in their ways and will, in essence, have blinders on which keep them from seeing how society has been progressing.
In reading the article about diversity, it is interesting to note that diversity has now expanded past outward appearance and includes the inner workings of an individual. We need to be aware of how society evolves and changes. This means that we need to adapt our teaching style to what is occurring to be considered inclusive.
In California, teachers have been required to go and obtain an ESL/TESOL certificate because it has become evident that the classroom now has a majority of students that do not have English as their first language. This is one example of what teachers are doing to re-teach themselves.
Basically, we need to continue our learning process as well as furthering the learning process of our students.