Professional Development - what's your favorite and not so favorite

Every year most of us teachers get a survey about our intentions for next year. 

Sometimes I've been asked what Professional Development I think would benefit our staff. This year is one of those cases. This year it feels especially important to answer this question because I really feel like my principal really listens to us when we make suggestions. 

I have sat through so many different professional development opportunities some which were so helpful and some which were a waste of time. As a teacher I know our time is valuable and that we are incredibly intelligent and usually know what is best for our kids without someone reading us some book they wrote or some ideology they have "discovered". While these PD's are important and I don't mean to down play these PDs in anyway, ones that are more valuable to our teaching and classroom are far better than just any old PD. I wish I could be a full time student and just sit in classes all day and learn - seriously if full time student were a job I would sign up! I absolutely love learning.

There are tons of different professional development opportunities out there are there any that anyone could suggest that they LOVED or didn't love I would appreciate hearing your feedback. 

Thanks for helping out in advance!