Most people will be traveling early or mid-day on the 6th day. As such, you probably won’t be doing much on this day. However, if you have some time, there are always many nice things to do.
In the past 5 days, you will have seen the major attractions in Paris, but you will have by no means seen everything. To see everything, you need two weeks to a month in Paris.
Below, I will mention a few other fun things to do, according to me. 🙂