There are a number of fun things that can be hung from a bar at the top of a doorway. It may sound funny, but it is true. You can find door frame support bars that can be placed at the top of a doorway, expanded and then locked to produce a body weight holding bar at the top. You may have seen this with the pull-up bars that you can get. These are similar.
With the right support bar in place, there are a number of different options you have for using it. One way to use it is for child swings and other child things. Often, kids can get bored with the usual activities of the house.
The younger they are, the more stimulation they will need directly from you. When you place a good swing on the support bar, you have a great way to interact with your child. Set it up as an indoor hammock swing with the right attachments and then cuddle up on a rainy day with your little tot and read to them right in the doorway.
Another way to use this kind of bar is for making a small home fitness system. You can do the standard pull-ups but also have straps and bands and such to create different exercises as you see fit. It is amazing the amount of exercise you can do with such a simple setup. It is not so easy to do the exercise but it is easy to get the equipment and cheap too.
While a home gym in the door and a good spot to swing the kids from is not everything you would need for a good day, it sure is quite a start for the bored kids or for you in the morning. Have more direct interaction with your kids and get fit too.