Beluga whales, frolicking dolphins, and sharks are the top draws at the Shedd. The first two groups swim in the Oceanarium, which mimics the habitat off the Pacific Northwest coast. For sharks, head to the Wild Reef exhibit, where two dozen ferocious, finned fish cut through the waters as in a Philippines reef ecosystem. The penguins toddling around the Polar Play Zone are another big draw.
General admission includes all of these exhibits. The 4D movie costs $5 extra.
In summer, you might want to purchase tickets in advance online to avoid the lengthy entrance queue (which can be an hour or so). Advance tickets provide priority entry for no extra fee, as long as you buy the tickets at least one day beforehand.