The two frameworks, however, differ in their views on the theory of learning as we describe below: Curriculum learning is inspired by the learning principle that humans can learn more effectively when training starts with easier concepts and gradually proceeds with more difficult ones (Bengio et al., 2009).
leitner system is inspired by spaced repetition (Dempster, 1989;Cepeda et al., 2006), the learning principle that effective and efficient learning can be achieved by working more on difficult concepts and less on easier ones.