My son is in 8th grade, too. He is a year younger than everyone else as he skipped first grade and he is very smart so he was teased and bullied terribly last year. I could see him getting more and more down and angry. We tried dealing with the school and it really wasn't a big help. It was not only verbal but physical and Geordie is not the type to fight. We took him out of school last year at Easter time and started homeschooling him. This year he is staying home again and learning via a long distance learning program our state has. His mood and attitude is SO much better. He is in Scouts which is a good program for boys, taking piano lessons and goes on field trips for school.
I will certainly keep your grandson in my prayers because I know firsthand how hard it is for these kids. I feel SO bad for them and get angry at the parents who don't teach their kids better. If he has email and would like a penpal let me know.