Redratfish already answered your questions, but I will give just a little advice since you left it open-ended.
As the camp is a non-Catholic one, I would say you have a responsibility towards your kids that they not be given false or confusing information on the faith. Being an “interfaith” camp, they probably strive for a “mere Christianity” type of atmosphere that sticks to the doctrines we share, but it’s always possible for anti-Catholic doctrine or sentiments to creep in. You do not necessarily need to be obsessive about it (depending upon the group), but you definitely need to keep it in the back of your mind so that you can do damage control if the need arises.
If I were you, I would also prep the kids in advance and make sure they understand the difference between a Protestant worship service and a Catholic Mass. I would also make sure the kids are familiar with our own morning and evening prayer (i.e. the Liturgy of the Hours). This is not to say we can’t pray with non-Catholic Christians, but we should be intimately familiar with our own rich heritage in this regard. Perhaps a lesson on the proper place of ecumenism in the life of the Church would also be beneficial.
I would also do a follow up to gauge what they took out of the camp and to give an opportunity to catechize on the nature of the Church. It’s good for your students to be able to get along with those of other faith traditions, but we don’t want them to get the impression that it really doesn’t matter whether you’re Catholic or Methodist or anything else. It
does matter, and they need to know
why it matters.
Does your diocese sponsor any youth events that are similar? If they do, it’s good for the kids to go to those events, too. If they do not, contact your diocesan office and recommend that they start one.