Khan Academy offers free education. Its goal is to provide learning and reviews on subjects such as Humanities, Science, Math, etc. However, since this platform is free, its offer is also limited and if you wish for something more advanced, it is suggested to check other education online course platform sites such as the following:
1. YouToken
Studying usually brings sleepless nights, stress and frustration in trying to understand complex data. YouToken challenges that by making learning fun and easier even with its complex studying materials. It ensures you are well prepared for anything at the same time less stressed while learning.
2. Udacity
Udacity’s specializes on subjects concerning Data Science and Technology. Though this might be a little intimidating, Udacity ensures its students are not overwhelmed by giving them decision to learn at their own time and pace.
Udacity also offers other subjects aside from Science and Technology.
3. Codeacademy
Codeacademy focuses on making learning languages easier. Slow or fast learner? Having a hard time catching up with others? Codeacademy allows its students to learn at their own pace. Its curriculum ensures you are able to apply everything you have learned by submitting a project at the end of the course.
4. Bloc
Want to have an advanced, intense and quick learning experience? Bloc is for you. It will teach you everything you want to know about web developing. If you wish to change careers, this site is highly recommended. However, if you decide to take up a course through this site, you will have to shell out a large amount but it is worth it. Just as everyone would say education is priceless.
5. Iversity
Iversity comes with prestige as it partners and works with European and international universities and since this is the case, you will be able to work with those universities as well. However, know that if you choose to enroll in this site, Iversity does not give legitimate certification.
Spanish 
English 
French 
German 
Turkish