Just wow. The Nagoya City Science Museum (NCSM) started off as an afterthought on my trip to Nagoya - the place I'd hit if I had some time left over. It ended up vastly exceeding all of my expectations and being one of the highlights of my trip to the city.
The NCSM is an enormous, six-floor building (not including the rooftop observatory or giant planetarium) that is stacked with engaging activities, hands-on displays, and more cool stuff than you'll know what to do with. While lots of it is child-friendly, it was the adults who were having fun playing with experiments about echoes, scents, outer space, and waves. Also, entry is really cheap!
In addition to the museum, the NCSM also houses an enormous planetarium with grand shows set at different times throughout the day. Tickets for these shows should be bought early, as they can sell out. On this visit (which fell on a national holiday), there were nearly 100 people lined up for planetarium tickets at the ticket window an hour before the museum opened, so plan ahead if you want to take advantage of the planetarium.
Each floor of the museum has a different theme, covering a range of topics that include the human body, technology, earth science, and energy. Each section is filled with elaborate and impressive exhibits. There's a "Tornado Lab" that creates really impressive nine-meter-tall tornadoes. The "Deep Freeze" lab requires visitors to put on special cold gear, and enter a room at -30 degrees, where they can watch a display of the aurora borealis (Northern lights). In the earth science area, watch water get cycled through creation, clouds, rain, and river stages to understand the water cycle. Play with voice distortion, telescopes, and liquid crystal. There is a lot going on everywhere you look.
The science museum is a great place to spend a playful day for families, dates, or even just groups of friends. Unfortunately, almost all of the information on the exhibits themselves is in Japanese only, but there is an audio guide system for multiple languages that is really useful. Also, the museum has a very comprehensive English website.
The Nagoya City Science Museum is located in Shirakawa Park. It's a five-minute walk from Exit 5 of Fushimi Station on the Higashiyama and Tsurumai Lines. It's also a short walk from Hirokoji Fushimi Bus Stop. There are also parking areas for cars and bicycles nearby.
The museum is open from 9:30am to 5pm (last entry at 4:30pm). It's closed on Mondays, and the third Friday of each month. Adults pay 800 yen for a combination ticket of planetarium + museum, or 400 yen for the museum only. For university and high school students it's 500 yen and 200 yen, respectively, while younger kids are free.