Paper masks are easy to make and can even be made by kids. However their life is limited to how long the mask will survive being used by children. An example of what I am describing would be this from HerFamilyTrends.com:
Failure is almost always going to occur from the elastic, string or yarn, that wraps behind ones head, at the punched hole. The holes usually wear out from the "string" and the mask falls off and needs to be repaired or discarded sooner. You can use something like scotch tape either before hand or after to make it last longer but the tension from the string will still cut into the tape and the result is still the same.
Sure, you could use something stronger like duct tape but that stuff is likely to get hair caught which is not comfortable.
What can I do to make the mask stay attached to their respective heads for longer while minimizing the need to repair it.