Cheapest priced copy (Strixhaven: School of Mages Promos): $0.49 at Card Kingdom, near mint, their price list as of .
Basic Conjuration 
Sorcery — Lesson · Rare · Strixhaven: School of Mages Promos · #120p
Look at the top six cards of your library. You may reveal a creature card from among them and put it into your hand. Put the rest on the bottom of your library in a random order. You gain 3 life.
Legal inCommanderPioneerModernLegacyVintage
Not legal inBrawlStandardPauper
4 printings · $0.49 to $0.79 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Strixhaven: School of Mages Promos | 120p | Rare | $0.49 | $0.79 |
| Strixhaven: School of Mages Promos | 120s | Rare | — | $0.69 |
| Strixhaven: School of Mages | 120 | Rare | $0.59 | $0.49 |
| Strixhaven: School of Mages | 315 | Rare | $0.49 | $0.49 |
2 rulings from Wizards of the Coast
- 16 April 2021Although you may want to include Lessons in your sideboard if you’re playing with cards that instruct you to learn, Lesson cards can be included in your main deck like other instant or sorcery cards.
- 16 April 2021Lesson is a spell subtype found on some instant and sorcery cards in the Strixhaven set. The Lesson subtype has no special rules associated with it.