Historical clue formulations

• Strikes on the noggin — 2025-05-30
• Bops — 2021-12-03
• Knocks on the noggin — 2012-06-19
• Hits on the head — 2005-04-20
• Funny hitting sounds — 2001-07-10
• Knocks on the noggin — 1998-07-21
• Whops — 1995-11-25