Otus. The first time that I saw it I was impressed by the functions that it offered. Since then Otus has steadily added more features and this week released a completely revamped web interface for teachers.
In addition to a more intuitive user interface some of the features of the updated Otus platform that jumped out to me include real-time analytics updates, third party app integration, easier seating chart movements, and easier recording of information. The improved analytics menu updates and recalculates as you record information about your students. This is true whether you're recording behavior and attendance information or you're recording scores from assessments.
Admittedly, it had been a while since I tried to update my student roster in Otus. When I went to update it today I found it was easier than before as I simply dragged and dropped student names into place on my seating chart.
Otus now allows you to integrate select third party applications into your account. A couple third party applications of note are Khan Academy and OpenEd. OpenEd offers thousands of math and language arts practice assessments aligned to Common Core standards.
If you're looking for a new online course management system to use in the next school year, give Otus a try. I think you will be impressed by the capabilities it offers.