I am traveling with a group of 30 students in June. We will visit the Paris area for 3 days.
Should we get a specific Navigo pass?
If your 3 days in Paris have you arriving anywhere from Monday to Thursday then a regular Navigo week pass for each student would be best.
I'm assuming you'll be making more than 4 one way trips on transport per day. If so, then the Navigo week pass definitely makes the most sense. Less than that, you could use a Navigo Easy card preloaded card and load it with individual tickets.
If you arrive Friday, then the Navigo week pass cannot be purchased/used for the current week, rather, only starting for next Monday.
If you arrive Friday, Saturday or Sunday, then Paris Visite 3-day pass for the either 1-3 zones or 1-5 zones (if using airports/visiting Disneyland) would be your next best option for unlimited rides (i.e. if you plan to make 4+ rides a day. Less than that, you could consider Navigo Easy, although that's much more of a hassle to purchase & load 30 cards vs. 30 paper Paris Visite tickets).