When I worked at a Miami, Florida arcade in 1982, the kids would ask for a "cased quarter" when they needed a quarter in exchange for two dimes and a nickle. The arcade games only accepted quarters. "The Amusement Center at the Omni Hotel" on Biscayne Blvd mostly catered to the local urban kids, and they were the ones that used the slang. I thought it was great and it made my job easier, too! I see that "case quarter" is listed, but my experience was with "cased quarter" with a d, the kids explained to me that the dimes and nickles were "cased" into one coin.
"Can I get a cased quarter please?"
Much easier than "Can I have a quarter for two dimes and a nickle please"