Cast a random Lesson spell without paying its mana color. If that spell has X in its mana cost, X is 3. (As of today, there are 20 lessons. Perhaps look up a list and roll a d20?)
Near Mint - $12.70
Lightly Played - $10.20
Moderately Played - $8.90
Heavily Played - $7.60
Damaged - $6.40
Near Mint Spanish - $12.70
Lightly Played Spanish - $10.20
Moderately Played Spanish - $8.90
Heavily Played Spanish - $7.60
Damaged Spanish - $6.40