We all know how difficult it is to identify the sex of these fish, so please post a picture in here and we'll try to help you (or at least give an educated guess!).
Here is a few pics of my 6 zebbys and i think at least one is a clear male and possibly one is a female.
The largest around 8 cm long and the smallest 4½ cm.
Number 1 i think is a clear male, number 2 i hope it´s a female and number 3 i think is a male to.
The small i don´t know yet, maybe they are to small yet.