EdX offers the "x-series" - https://www.edx.org/xseries https://www.edx.org/xseries - and Coursera offers "specialisations" - https://www.coursera.org/specializ

EdX offers the "x-series" - https://www.edx.org/xseries https://www.edx.org/xseries - and Coursera offers "specialisations" - https://www.coursera.org/specializations https://www.coursera.org/specializations - they're charged per course. According to them, when you pay the $50+ per course, your completion rate goes up dramatically, to something like 70% - probably due to the fact you've paid something for it.