Have a look at the impact volunteering has on young people, but also on the volunteers themselves.
Volunteer roles

Judge - Innovation Project, Core Values or Robot Design
Suitable for: Anyone with an interest in encouraging young people into STEM. Robot Design Judges preferably have a background in robotics/programming.
Amount of time required: Attendance at tournament day(s), possibly a couple of hours training.
Involves: Interviewing teams about their work or their application of the FIRST® LEGO® League Core Values. Providing positive, along with constructive, feedback and ranking the interviewed teams with a view to selecting the award winners.

Robot Game Referee
Suitable for: Anyone with an interest in encouraging young people into STEM. No specialist background required.
Amount of time required: Attendance at tournament day(s), possibly a couple of hours training. Preferably, referees would spend some time learning the Robot Game rules leading up to the event.
Involves: Observing team robot games, assessing field for scoring of matches and participating in deliberations regarding contested calls and official scores. Referees play a critical role in ensuring smooth flow of match play, maintaining the pace of the event, and providing encouragement and recognition of the teams’ achievements.

Team Mentor
Suitable for: Anyone with an interest in encouraging young people into STEM. An up to date DBS check may be required.
Amount of time required: One to two hours per week/fortnight from September until the team’s tournament.
Involves: Attending a team's meetings as they work on their project and robot. Motivating and focusing them. Providing guidance whilst ensuring that they find their solutions themselves. Acting as a role model for FIRST® LEGO® League’s Core Values.