Integration with other systems

I am a software developer and I provide school management software for some small towns, for enrollment, class records, assessments, etc.

I want to add Khan Academy content to my software, so that each subject and each course of each class in my system can be linked to the content to be trained or taught on Khan Academy.

What is the best way to do this? Is there an API? Can I just use the course links?

I would appreciate any information.