Go to the health park! The environment there is relatively good, with hot spring bathing, swimming, skating rink and so on. Tickets are around 39 yuan, and there are also large lounges, recreation rooms and some activities that require extra fees.
In the evening, you can go to Jinghua Garden, where there are various national performances. If you go now, there will be a large water-splashing festival, which will last for two months.