Lagunitas School District trustees voted last week to put a parcel tax on the November ballot—critical funding for the district that still won’t balance an ongoing budget deficit that officials say is rooted in an unusually high number of special-needs students. Without the tax, the district says it would have to cut about a fifth of its budget, over $650,000, a move that would undoubtedly lead to layoffs.

The parcel tax would renew a previous…