Paperwork, paperwork, paperwork. Seems like just a lot of busywork until something is needed - then the paperwork is a lifesaver. A quick assignment for this week: Make a copy of your originals and give them to your group leader.
Copy of your passport
Copy of medical insurance cards
Copy of your visa (if applicable for you)
Parent Consent Form - for minors traveling without parents (this needs to be notarized)
https://www.us-passport-service-guide.com/support-files/minor_travel_consent_form.pdf
(or this site will walk you through step by step completion of the form - but you will need to sign-up for a free week trial login https://www.lawdepot.com/contracts/child-travel-consent/#.Wk-nISPMyi5)
Passports need to be thought of as gold. You don't want to lose yours or have it stolen. If you are a parent of a mission trip member, please emphasize this point to your teen and maybe plan ahead with them how they will carry their passport or if it is better for the team leader to carry their passport.