Comment by TrainedMonkey

Both coursera and udacity have amazing courses on crypto.

Udacity: https://www.udacity.com/course/cs387

Coursera crypto I: https://www.coursera.org/course/crypto

Coursera crypto II: https://www.coursera.org/course/crypto2

I took coursera crypto I myself. It was a lot of work, but I learned a ton.