Well, you've got your hands full. Here's a few thoughts to kick around. You have to do something to control the light to keep the tonal range within the dynamic range of your recoring media (digital or film). If you don't there will be no such thing as proper exposure. Two things to use to do this are a large diffusion screen/panel and reflectors. A diffusion screen is a large piece of thin white fabric or translucent plastic (a shower curtain works), stretched over a frame. The screen is paced between the sun and the subject to soften and reduce the intensity. PVC pipe is good because you won't have to glue all the connections so you can break it down for transportation. You'll need a panel that is at least 1 x 2 meters in size. The other thing you need is a reflector to open up shadows and give nice catch lights in the eyes. White and, or gold, would be good. Again, large is good: a square meter would be an appropriate size. If you're wondering how you're going to work all! this by yourself, you aren't. You will need an assistant on this shoot, for this and several other things. Exposure: If you shoot digital record in RAW mode, since this will give you the best chance of touching things up latter. Use a handheld incident meter and work in manual exposure mode. Once you get the exposure right (checking histograms and such) you only have to change settings if the light changes. Your assistant can keep tabs on the light with the meter. Reflected light readings will vary with every outfit change, and throw things off. You will also keep the backgrond looking consistent from shot to shot with manual. Between now and the shoot get in as much time as you need to get the technical issues resolved doing test shots and experimenting. Your shooting schedule will go right down the toilet if you have to solve major technical problems in real time. Somebody, besides you, will have to do kid wrangling to make sure kids are in the right outfits, look good and be ready to be shot at the right time. Kids who are waiting to be shot will have to be kept ammused and comfortable. Make sure there will be enough folks around to take care of things so that you can concentrate on shooting.
Good Luck. BR
