Google Summer of Code (GSoC) is an annual, international, program which encourages college-aged students to participate with open source projects during the summer break between classes.
Students accepted into the program receive a stipend, paid by Google, to work well-defined projects to improve or enhance the Jenkins project. In exchange, numerous Jenkins community members volunteer as "mentors" for students to help integrate them into the open source community and succeed in completing their summer projects.
Although we use mailing lists as the main communication channel, we also define regular timeslots aka "office hours". During these timeslots Jenkins GSoC org admins and mentors will be also available in the Gitter channel. Video calls will be conducted on-demand.
In addition to these meetings, each GSoC project has regular meetings during community bonding and coding phases. See the project pages for the schedule.