Prison inmates have been listed among the best-performing students at the National Open University of Nigeria.

This was according to the spokesperson of NCoS, Abubakar Umar, while quoting the NCoS-NOUN Special Study Coordinator, Controller of Corrections, Francis Enobore on Wednesday.

The statement reads “Inmates in correctional facilities have distinguished themselves as some of them are among the best-performing students in the university."

Full Details at News Source: https://www.zionie.com/read/prison-inmates-make-the-list-of-best-performing-students-at-open-university

It's the same worldwide. They have nothing else but studies to distract themselves. Of course they'll do well. In the US, many attain high school diplomas from prison stints.

If they were more intelligent, they wouldn't be in prison
Prisoners don't just have jobs or family responsibilities to attend to; so they should perform better academically.