The paper presents a meaningful discovery learning environment called "cache-cache comparison" for a personalized learning support system. The processing of seeking hidden relations or concepts in "cache-cache comparison" is intended to encourage learners to actively locate new knowledge in their knowledge framework and check the logical consistency of their ideas for clearing up misunderstandings. This active engagement is also expected to prevent a) the emergence of cognitive overload and b) the decreasing of the curiosity and willingness to explore as in the meaning reception learning environment. [For the full proceedings, see ED562093.]