In addition to JumpstArt, there are other summer opportunities that LG has sent students to in the past.
Some of these include:
CCA - California College of the Arts
SCAD - Savannah College of Art and Design
MICA - Maryland Institute College of Art
(click the above links to go to their pages)
But there are even more:
Academy of Art SF
Otis College of Art
Laguna College of Art & Design
RISD - Rhode Island School of Design (super intense)
It's good to know your options.