I have kids nearly the same age, and we just moved to Hangzhou mid December from Shenzhen where we arrived in August. Must bring items I think depend on your kids as nearly everything is made here. I brought their video game consoles, but bought new leads to accomodate different wattage here. Internet access: because we came from the States, Netflix is an essential. We paid for a high speed internet with vpn built in, which works fairly well. And when it doesn't, it is reset remotely. We arrived in Hangzhou during the holidays, so it seems everyone is out, but I believe I found a great football org for my son, and still waiting for dance links for my girls.
I will let you know as I learn. Happy New Year by the way!