The actual cost from the chalksite.com website specifies;
How much does it cost?
Chalksite is available in 5 different plans ranging from a completely FREE plan to pay plans ranging from only $4.95/month - $19.95/month. There is also school pricing available with discounts up to 35% off.
Check it out (from the title link);
While attending college, the student control panel was the one thing that I always felt my educational system just could not get right. Every student was given access to a control panel that had been built to help students keep track of schedules, important dates, finances, email, and announcements, and I am sure the average college provides students with this as well. This is great, although I personally found it confusing, horribly crafted, and pointless (I really didn’t like the control panels during my college education). So, what were these systems lacking? I feel they were mostly lacking student/teacher communication. Whether I had to catch up on missing assignments, ask a question, keep up with grades, or whatever the case may have been, I had to email the teacher. Now, the problem with this is that I had to wait for a reply, the teachers had to put time and effort into making a reply, and not to mention teacher email accounts were built into the control panels as well, which teachers weren’t too fond of either (funny). What I am getting at is communicating was a handful and had always seemed to be more troublesome then it should have been in an educational system.
Chalksite solves this communication problem by providing teachers with an easy to use central point where they can communicate with students and parents, post assignments and grades, send messages to each other, and even manage a website for their courses. However, so there is no confusion, Chalksite is not a learning system like Nuvvo. It is more of a system to organize and communicate rather then a full-fledged system for teaching. This is what I like about it though and it definitely is a service that I would have absolutely loved to use back when I was attending college.