A dvd copy for each participant is still an excellent idea, even in the age of vimeo and youtube. It gives genuine ownership of the project, and allows young people to show their work to friends and family (a real confidence boost, especially important if they are underachieving in other subjects).
If you are in a school, and produce films regularly, you might consider only having an online only version. If it is not you, find out how you can get the film embedded into your school site. Even more important than duplications for the participants is a screening.
sleeve design
Working with participants on a cover can make the dvd box look great, and become a class marketing and design exercise.
archiving the project yourself
It is cheap to produce copies yourself, however feeding dvds into a machine is pretty mind numbing. If you are making over 30 copies consider a duplication house.
duplication houses
Quadrille Video Duplications Ltd
A helpful Scotland based dupes house, who can also do fancy things like NTSC format for the USA. 0131 667 1064
Video-Tec Group PLC
Are an organisation who provide reasonable, economical service www.vt.tv you now have to deal with them online because their number is a premium
0700 000 2345