Here is a small selection of what I reckon are top quality probability sites of interest to high school teachers;
This is a treasure trove of resources that can help enhance your teaching of probability and statistics. You can easily keep in touch with the developments on this site by subscribing to the chance newsletter.
Lots of innovative java activities. I especially like the animated birthday problem activity.
Loads of well-structured java activities. Well designed for the classroom.
Loads of well-structured Excel activities. Well designed for the classroom.
This guy writes fantastic maths activities that are hard to beat. I like this one on conditional probability.