having trouble figuring out if my afghany is male or female help!!

well i am leaving to go home today, we had six plants one is definitly a male so its out, but the afghany goo, i just dont know. i dont see any pistons but i dont really see a sack yet. its been growing for like 5 months so i cant tell if there are pistons growing or if its the beginning of a leaf set. is there anything i can do? i dont know when ill be back someone is going to water the babies but i do not think she has any idea what the difference between a male and female is. so i kinda need to know today?