A dark / changing bag and a Daylight development tank from Paterson System 4 are probably your simplest option.
You put everything in the bag, you stick your hands and transfer the film to the coils for development, place the light trap tube with the coil in the tank and close the tank with the funnel. [Sheet film has a few options, but is doable in the same mid to large tanks]
From there, you can do the rest of the steps in the light of day, where it's easy to share them with a class.
- Black and white film and chemistry are easy to use, relatively indulgent and inexpensive.
- Color film is an option, but requires tighter controls and is more expensive for smaller batches.
From there, scanning negatives is a good option to import into a modern directory workflow.
Other options include the use of "paper negatives" and exposure to black and white photo paper.
- These can be developed under a safe red light that students can follow.[Noiretblancmodernenormal[Normalmodernblackandwhite[Noiretblancmodernenormal[Normalmodernblackandwhitemovie reacts to red light and must be handled in total darkness or possibly with infrared glasses if you do not handle infrared film]
The third common option is to use "positive direct paper", almost identical to working with normal paper negatives, but they have "normal appearance" once you have developed them. – The extra cost over paper negatives is probably not worth it if you digitize and reverse the image numerically.
Use an Instax movie or a Polaroid movie is possible, but has additional obstacles to overcome in order to develop them reliably, and costs more per photograph. You will need to develop a method to run the film through a roll to develop it.
- However, this may be an option if you are very enthusiastic Color images and do not want to send a film to a lab or deal with the more capricious color chemistry.