We have three nights in Shanghai with one planned day and one free day. It is the most amazing city, I first visited in 1978 on business with my mother and how the city has changed!
The Bund is less than 15 minutes walk from our hotel.
On the free day there are plenty of options right in downtown Shanghai. The Yu Gardens are quite close by to our hotel, but you will be best to get there early before the crowds arrive. Lots of parks and gardens nearby to see the locals dancing, doing Tai-Chi etc.
More suggestions will be added here very soon
You can also consider going further afield for the day like Suzhow and Hangzhou
Take a look here at the different options Shanghai Day Trips
Please message me if you have any questions