What colleges will accept a high school diploma from PennFord High School?

Answer 1: Penn-Foster High School is "regionally" accredited. Therefore, any and all colleges and universities in the US will happily accept its high school diploma, just exactly the same as if you had obtained the diploma from your local regionally-accredited neighborhood high school.

"Regional" accreditation, by an agency approved by the US Department of Education (USDE) (which is the kind of accreditation which both Penn-Foster High School, and your local neighborhood high school, have) ensures that alll colleges will view both high school diplomas exactly the same... and will accept either, equally.