On a budget, Art Institute of Chicago still earns its price.
$26–32 adult
A genuinely world-class collection where you can stand in front of Seurat's 'A Sunday on La Grande Jatte' and Hopper's 'Nighthawks' in the same afternoon. The catch is scale and price: it's a half-day commitment and easy to burn out, so pick a wing rather than trying to see everything.