LANSING, Mich. (AP) — Michigan is waiving more public schools from a decade-old law requirement to open after Labor Day — a nod to increasingly popular year-round schooling, the addition of more mandated class days and other factors.

In 2006, the first year in which August start dates were legally off limits, the state Department of Education issued nine waivers. More than 10 times as many exemptions were granted for the last school year.

The trend alarms tourism officials who successfully lobbied for the post-Labor Day law. But some legislators say it is evidence that the requirement should be revoked. Michigan is among just three states to require starting school after Labor Day.

A state spokesman says the driving force behind waiver requests is schools wanting a year-round, or “balanced,” calendar.