Conventions and Circuit Assemblies are awful, boring, day or several day-long events conducted sort of like a horribly extended Sunday meeting at the Kingdom Hall only with lots more people in a big stadium. You must dress as if you are going to a regular meeting (women and girls in dresses, men and boys in suits...little boys can get away with just nice slacks and shirts).
You sing and pray at the beginning, you listen to several hours of talks, you break for lunch for about an hour and a half (eating your sandwich which you brought from home...and then you can get up and socialize). When lunch is over, you sing again, listen to announcements (usually saying that your Circuit is already in the red and they need more donations to cover costs), and have the whole afternoon full of more talks to look forward to while trying not to nod off.
On Saturday or Sunday afternoon (I can't remember any more) you get the super duper treat of watching a drama...this gem is usually a hommily demonstrating the wisdom of following Watchtower instructions in living your life...where the actors (your brothers and sisters from your's and other congos in your circuit) dress up in Biblical garb, mouth the words to a pre-recorded tape and wave their arms around like the robot on Lost in Space.
You do not leave your children out of this special time. They must come and learn to sit quietly in an uncomfortable chair while listening to stuff that they don't understand for hours and hours and hours. If you are lucky, the poor things will fall asleep.