what's everyone thoughts on emphasizing takin charges? I've always done this, but lately I'm very frustrated by seeing my players stand in and sacrifice their bodies only to get called for a block and send an out of control offensive player to the foul line. I just wonder if it's worth the time and investment for little return?

I always taught to take a charge also.... we were usually the underdog so there were two points of empasis here...
1- take a charge
2- get every loose ball

Even IF they called it a block and put something in the mind of the guy going to the basket that someone was there to stop them.... it might change their shot.... hopefully you will get some calls soon. You might even plant the seed in the mind of the refs before the game... ask them about the charge / block calls... and what exactly do your players need to get the call?? Tell them you just want to make sure that you are teaching it correctly.
Here is a great drill..
http://www.youtube.com/watch?v=_ThNuTR83IM

Loose balls.... get every one, that gives you another possession. These two things are what I called GAME CHANGERS.

Good luck and I hope this helps.