I took my boys ages 8 and 7 on a Saturday. The biggest mistake was going on a Saturday while China is out for summer break. It was very crowded and those children were rude. They tried several times to cut in lines with their parents full support. The museum it's self is wonderful. It is about 5 stories of information. They have interactive things for kids to play with and most everything is written in English as well as Chinese. We spent at least 3-4 hours in the museum. Some might not need as long but, I love museums. Do bring water with you. We got thirsty and asked about drinking fountains. That's when we were told we needed to bring our own water in with us. It is a quick walk from the Tsim Sha Tsui station on the Red line. Also be forewarned the MTR is crazy busy. You will get pushed and manhandled if you decide to take it. Overall the science museum is inexpensive (compared to the rest of Hong Kong) and worth the time.
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