Grp. putting together résumés, likely

• Sophomores, two years later: Abbr
• Some upperclassmen: Abbr
• Messrs., in Madrid
• Gp. receiving diplomas
• A.A.R.P. members
• Upper class: Abbr.
• H.S. "ruling" class
• Many SS recipients
• Coll. hopefuls

Wiktionary Word definitions in Wiktionary
abbr. (context texting chatting English) (abbreviation of serious English)