If you're a fan of live theater performances, book yourself a seat for a play at Theater Sebastopol. Check online to see what's still available.
You'll have no end of sightseeing choices in Vauban - Wazemmes. Theater Sebastopol is a great place to begin here, but there are numerous other interesting spots to check out. Lille Grand Square, Rihour Square, and Citadel of Lille are close to the arts and culture attraction and will top off your day nicely.