Shoot portraits of 100 children in 3 hours (and get decent results)

It is becoming a tradition that around Xmas and new year a quite big photo event is organized at the school where my wife teaches. The idea is to take a 'Christmas-like' portrait of each child in the school and offer it to sell just before Chrristmas so the parents and grand parents have something memorable (next to the other gifts).
Each year it is quite extensive photo session, since there are 100+ children, each child is photographed twice (the whole silhouette, and a shoulder portrait), then there are always group photos: with best friend, with the whole class, with the group of buddies, etc.

This entry is not about shooting portaits. There are dozens of places where it is already described (like here).
What is not said very often though are the little details around the session that can save you a lot of time if applied. And the opposite applies as well: if forgotten, a lot of extra work needs to be done during and after the shooting.

Over the years I have established kind of a 'logistic workflow' ensuring that the session goes smooth and the children get their photos a week or 1 1/2 week after the session. Here are some things that work good for me:

• Make appointment in advance. Inform the teachers about the event. Kindly ask for cooperation during the event
• Plan the whole event. Ask for the day schedule in advance. You want to shot all the children being at school this specific day. Look at the schedule and check if it is possible, and how to order the classes.
• Work with small groups. Try to avoid the situation when 20+ 7-years old boys and girls are running around (and sometimes across) the shooting setup. See also next bullet.
• Ask for the assistance of some staff or parents. Believe me having 2 other adults that children are familiar with is priceless. They organize smooth flow of the groups, keep an eye on the group waiting for the shoot and they can assist immediatelly in case something unexpected happens.
• Have a feminine assistant on location. For one important reason: women pay a lot more attention on the small details with respect to children hair, clothing and general look. And they can make 'last minute' small adjustments in a way that children accept it and feel comfortable.
• Play safe with your setup. While it is tempting to start experimenting with your beautiful models (as children of all ages are), remember that there are 100 waiting for their shot. So what I use mostly is a simple lighting setup with a softbox at the front of a model and one to enlight the background or to create separation between a model and the background. Something like this:

• Take a steam iron with you (no kidding). It happened to me that after unfolding the background and putting it on the stand there were creases going right through the background scene. Sure, you can remove them in postprocessing but remember: You'll have to postprocess 200+ photos. Believe me, after 10 of them it is not fun anymore. Ironing of the background will cost you 15-20 minutes.
• Take a big, white sheet with you. When put on the window it can soften harsh light (you never know) and form a nice, additional light source.
• Talk to children. Some of them seem to be born models. But some need just a little encouragement. 
• Ask children to bring their favorite toys. While not always necessary, sometimes it enriches the scene and makes children looking more natural.

This year after first shooting session one of the parents invited me to her school to make some photos at their place. Apparently she liked the photos. Which is very nice.