There are some that have "access control" like some netgears routers which can do about what you want.
You can turn it on and choose default setting: allow or disallow new devices to connect
Review the list of devices that have tried to connect and block/allow them.
If your router has no such feature, you are pretty much limited to one of the following:
-Don't tell people wifi password, except the ones that can connect.
This can lead to person telling person B the password and/or multiple users/machines connecting.
-Set up a Mac address based access list in addition to password.
This limits the machines that can connect but.. you have to type in the allowed mac addresses by hand yourself and get the people to tell you their mac address.