Shanghai Science and Technology Museum:  Architecturally stunning, huge, and world-class in every respect.  This is one of the world's largest science museums and its sheer scale personifies China's aspirations to be a global leader in science and technology.  There are numerous exhibits in several themed areas, including a reproduction of Kunming's Stone Forest, a trip to an underground coal mine (minus the accidents!), a creepy spider exhibit, space exhibits, and a "Light of Wisdom" room with numerous hands-on displays and a kid's play area.  In addition, there is an IMAX theatre as well as two additional virtual reality theaters.  A food court in the basement offers excellent Chinese food at reasonable prices.  Adjoining the museum is a nice park to relax, people-watch, or fly kites, and the New Xiangyang Fashion and Gifts Market, a huge underground market where you can get great deals on clothing, luggage, jewelry, and accessories (assuming you bargain aggressively).  The easiest way to get here is to take Metro Line 2 to the Science and Technology Museum stop.

Shanghai Urban Planning Exhibition Center:  This four-story museum in the heart of People's Square chronicles Shanghai past, present and future.  There are excellent photos of Shanghai's glorious past juxtaposed with the same view in the current.  The highlight is a huge scale model of Shanghai's cityscape as city leaders see it in 2010.  In addition, a 360 degree theatre features a computer-generated fly-through of Shanghai in the future.  This museum is a great introduction to Shanghai and provides a good appreciation for the breathtaking speed of development happening all over the city.  In the basement of the museum there is a replica of a typical Shanghai street in the 1930's, with little shops and cafe's selling snacks and trinkets.  Fun for a quick stop and photo before heading across the street to the huge Raffles City mall where serious shopping can be done.

Shanghai Ocean Aquarium: Behind the Pearl Tower, this aquarium has the usual displays but its claim to fame is a very long underwater viewing tunnel, which takes you via conveyer belt through various ocean environments.  Keep in mind that the underwater tunnel is the last display in the aquarium; once you're through the tunnel, you can't re-enter the aquarium.