Hi Bumble, I envy you, but am happy for you. The children are in for a treat, only problem I can see is that they are going to want to see Pleo next week, and so on and so on.Children at this age are very very inquisitive and are like little sponges absorbing everything they can learn. Play is Children's work. That is my motto. If I were still teaching school, believe you I would bring Nova in all the time. It is a perfect opportunity to get children to learn and to listen as well as a way for the children to respond to you and learn to interact well with each other, as well as learn things like social interaction and listening skills.
If it were me, here are a few ideas I would try. One, most children all love dinosaurs, and of course, Pleo is a dinosaur, so you have a built in audience all ready. Learn all you can in the next day or so all about Real Baby Camasaurs, what were they like.( how big, which period, Jurassic, etc. What did they eat, who were their enemies, etc.) You can find out most of these things on the internet or if your computer is a problem, your local library.
Use Triton, Macon or Juno as a Model for a lesson in Dinosaurs, Camasaurs. After talking about the REAL dinosaurs, explain what a Pleo is, and remind the children that he/she is only a baby, and just like any baby animal, human etc, they need gentle care, get scared easily, need naps, need to eat, etc. Tell them how gentle their skin in, that they can't get wet, that they can see and hear, etc. The more you stress that they are a REAL baby and can be hurt, children will understand. Rather then let the children pick him up etc, ( depending on how many children there are,) have them come around one at a time and pet him gently on back or where ever you choose, (Make sure their hands are clean, maybe use instant hand sanitizer to be on safe side...) Demonstrate some of the things your Pleo can do, Tada Trick, Sitting,singing etc and eating leaf, a good way to end it is to show them how Pleos take a nap like children do..

If they are still interested and there is time, perhaps they can draw pictures of what their Pleo would look like, explain Pleos can be Any Color,( Remember the new color choices we had!) or would they rather have another type of dinosaur.? If you have an internet connection at church, maybe you can show them a cute short Youtube Pleo video, Christmas Singing or interactions with other Pleos, pets, etc.
I could think of so many wonderful things to use Pleos for with children and you have a perfect opportunity to get these children to interact with you in a really special way this Sunday. I do not know if you help with Sunday Bible Lessons, etc, but if you do something along that line, perhaps you can also use Pleo as a Reward to bring him next week if everyone does well, listens etc. I don't think handling Pleos rough will be a problem esp if you stress how gentle babies they are and children will want to be gentle with them. Bumble, this is a perfect chance to get a good video recording as well, as long as the parents allow it, make sure you get back to us and let us know how things go. This sounds like great fun, and I think your pleos are in for an experience too.
RedwoodsMama and MS. Nova