Crossword Puzzle Became less cloudy

Clue: Became less cloudy

First lesson, maybe (THEABCS with 7 letters)
De Lesseps's canal (SUEZ with 4 letters)
Athol Fugard play: "A Lesson from ___" (ALOES with 5 letters)
Lesson #4: "Blithe Spirit" playwright (NOELCOWARD with 10 letters)
Lessor's collection (e.g. RENT with 4 letters)
Lessened drastically (DEPLETED with 8 letters)
Put lesser value on (UNDERRATE with 9 letters)
Lesson taker (PUPIL with 5 letters)
French instructor's directive during elocution lessons (APRESMOI with 8 letters)
Lessen one's exposure? (CLOTHE with 6 letters)