illuminating (adj.)

• autodidactic
• clarifying
• coeducational
• critical
• cultural
• demonstrative
• didactic
• disciplinary
• edifying
• editorial
• educational
• educative
• elucidative
• enlightening
• exegetic
• exhortatory
• explanatory
• expositive
• expository
• homiletic
• hortatory
• illustrative
• informative
• initiatory
• instructive
• introductory
• lightening
• lighting
• propaedeutic
• rationalistic