Finding challenging material for profoundly gifted children can be difficult, particularly when students are working at a college level. Consider carefully whether MOOCs might be a good fit. You can find more information about MOOCs in my post, Massive Open Online Courses [MOOCs] For Homeschool Students.
EdX works well with younger students who are profoundly gifted and need a challenge. EdX will verify their identity (with passport or state ID), and allow them to purchase verified courses and issuing certificates of proof. This added step will help keep younger kids safe by not allowing communication with other students taking the class and otherwise masking their personal information. EdX offers classes developed by prestigious colleges and universities.
Udemy also allows younger students to use their platform, and will also issue certificates. While their policy states that users must be 18 years old, a parent is permitted to register and then enroll a child under 18 into courses that are appropriate for them. They recommend that students use an account with adult supervision. If they need certificate information changed, that can be done too. Udemy accepts teachers as young as aged 18, and without the backing of a university.
As always, parents must carefully monitor online behavior to prevent high risk situations with their children. Keep computers in an open area of the house, facing public areas, and check online student interactions. In addition, parents need to carefully monitor the amount of online media consumed by a child overall, so they have a balanced workload without excessive digital instruction.
I hope this helps you understand using MOOCs. They can be a great resource, but like everything, should be monitored.
Have you used MOOCs with your student? What has your experience been?