Clingy

My almost 4 year old has all of a sudden become super clingy when it comes to dropping her off to places such as Primary and Preschool. She's NEVER been clingy before, in fact, quite the opposite. I'd describe her personality as: independent, hard-headed, and spirited.

Initially she transisitioned beautifully into Nursery, then Primary, even dance. But just as of late she seems to be testing her boundaries or something, as she won't let me leave her sight!

Primary is difficult because I'm the 2nd counselor and am in there where she can see me and whine for me. So I can't just drop her off and leave it to her teachers to talk to her; I'm standing at the front teaching Sharing Time or running around in the back as she's clung to my leg! Hello! How old are we? Which makes me think she's just testing boundaries. But how do I remedy the situation and let her know where those boundaries are?