Show classes with no time as not having a time (i.e., not showing 12:00-12:00)

Is it possible to allow classes that do not have a time (but need to be in the system for info - i.e.: solos, duos) to show up with no time? Currently, they show as 12:00-12:00 and that is very confusing for parents. It doesn't matter if I select the '0' option for the time slot, the program automatically changes it to 12:00-12:00.