The Kwik Student course has elements from both Kwik Reading and Kwik Recall, but also includes other elements for studying school subjects.
Kwik Student is geared toward students, though not specifically children. It teaches a mixture of speed-reading, memory, and studying skills like note-taking and focus. Kwik Reading will have more speed-reading training than Kwik Student, and Kwik Recall will have more memory methods and training than Kwik Student. So it's really a matter of if you feel you would benefit more from having a bit of all three, including the study techniques, or greater focus on any specific area.