One of the great things about the Web is free software. No matter how specialized your needs, something is probably out there.
Teachers can really benefit from this largesse. Some have numbers of students and paperwork to rival a small business.
They will likely find Moodle helpful. This course management system is a free, open source package. It can be used by one teacher, or by a university with thousands of students.
Because Moodle is open source, anyone can modify it. Those with programming skills can add features they want. Others can request changes in Moodle's Message Board area.