I spend much of my time working with K-12 teachers around the use of technology to teach math and science. Leadership is one of those slippery words, like vision or assessment. It seems to mean different things when one person says it and other person hears it. This is much more than putting on a flashy presentation or using the moment to reinforce your self-image. Being consistent is awfully hard in this arena, because you are often ready to move on to something new before your audience is.
Leadership also means working with a variety of stakeholders in a situation.
You can't just focus on the teachers, the administrators, the school board, the parents, or the students. You need to find a way to engage a variety of folks to help bring about change. Another lesson I've learned is that you can teach old dogs new tricks, but you don't do it in the same way as you do with younger dogs. In the past year, I've been giving basic technology workshops for local teachers. The average number of years of in-service experience has been close to twenty for participating teachers.