Senior ditch day may be a longstanding tradition in local high schools, but every time a student misses school, whether it's an excused absence or not, it costs the district money.
This year, each of the four high schools in the San Ramon Valley -- Cal High, Dougherty Valley, Monte Vista, San Ramon Valley -- had a ditch day, usually the Monday after their prom, according to district spokesman Terry Koehne.
"They all do have some sort of unwritten senior ditch day," Koehne said. He estimated the district receives about $28 per day from the state in what's called average daily attendance funding.
Koehne compared the number of students who missed school on senior ditch day with a random day, April 12. On that day, 85 seniors throughout the district missed school. On senior ditch day, 285 seniors -- or about three-and-a-third times as many as the random day -- were absent.
So, on any given day, the district may lose a little over $2,500 in ADA money, while on senior ditch day, the district lost just over $8,200.
By comparison, the Pleasanton school district lost just over $42,400 for senior skip days at its two local high schools. That district loses $51.54 in state average daily attendance money for every day students don't attend school
But Koehne said it's not just about the money.
"It absolutely is significant, if for no other reason, education," he said. "We'd like to have students in their seats all day every day."
That, he said, even applies to seniors who have earned the credit they need to graduate.