The IRIS-HEP Fellows program provides summer projects for undergraduates to work remotely with experienced researcher mentors on research software projects and for graduate students to travel for 3 months to work with a mentor.
The HEP Software Foundation is a mentoring organization for Google Summer of Code. Students from around the world can apply to work remotely on a variety of research software and computing projects with a experienced mentor.
The US-ATLAS SUPER program provides undergraduates associated to U.S. institutions the opportunity to work with research mentors on topics related to physics analysis and related software and computing tools.
CERN also runs two summer student programs where Bachelor or Master students will get experience on a variety of topics in the fields of theoretical and experimental particle physics, engineering and computing. The main student program is normally aimed at students from CERN member states, whereas students of all nationalities can apply to the CERN openlab program.