My mother in law gave these to me. She graduated from Atlantic city High school . The twenty dollar piece is engraved
" ACHS 25th Reunion 1974"
They measure 3" Dia X 5/32"THK and have mold seam around perimeter.
Yes, these are souvenir coins. They were pretty common at amusement parks when I was a kid. (not sure about these days) I had a penny that my parents bought me like 40 years ago from Magic Mountain if I remember correctly.