The Lagunitas School is facing a mounting deficit after a recent law forced it into a financial predicament. Until last year, the school’s spending was in good shape, buoyed by the San Geronimo Valley’s booming real estate market and a smaller enrollment. But then changes to state education finance law saddled the district with the cost of valley students attending the Ross Valley Charter School in Fairfax.
This year, the district is paying $138,000…