Each intern has a dedicated weekly one-on-one time with the mentor they are assigned. They usually discuss the current project, the issues and questions the intern has and how they can improve.
Each mentor has a dedicated weekly time for the group they are mentoring. They discuss general issues about the technology they cover, news and major features, what literature to be read and webinars to attend.
Each client team has daily scrum meetings with the mentors, usually for 10 min. They discuss the tasks done the previous days, the tasks they will do and if they need any help or have issues to solve.
When needed, if an outside mentor need to be included or the mentor is not at the office, we encourage all types of communication. Video conferencing has proved to be most effective.