Andrew Hertz sure wishes summer vacation didn't end so early this year. He'd rather have more time for summer camp and playing at the Miami Seaquarium.

''We've lost a week of summer each of the last two summers,'' said the 38-year-old general manager of the Miami marine park, which offers weekly day camps in June, July and August. ``Normally there are 10 weeks of summer, and we get 10 weeks of summer camp.''

Kids aren't the only ones grumbling about school starting on Aug. 8 this year, eight days earlier than in 2004. Museums, theme parks and other tourist attractions say shorter summer vacations take away part-time workers, complicate family travel plans and cut into summer camp attendance, a key source of seasonal revenue.

''It basically means we lose a little bit of our earned income strength for the month of August,'' said Kim Cavendish, president and chief executive of the Museum of Discovery and Science in Fort Lauderdale, which cut back its camp schedule this year by a week.

Wanting to start mid-term exams before Christmas and give students more time to study for the FCAT tests in the spring, Broward and Miami-Dade school systems have moved the start of school from late August to early August. That puts the region largely in line with most of the state; only six districts start later than the week of Aug. 8 to 12, according to the Florida Department of Education. (Monroe County starts school Thursday.)

With 67 school systems each picking their own first days of school, Florida's tourist attractions have pushed for a more uniform start closer to Labor Day. Staggered openings leave some attractions short on local high-school workers to help with the seasonal rush, while other parts of the state are still in full travel mode for summer vacation.

''It's kind of a double whammy,'' said Donna Ross, president of the Florida Attractions Association. ``We tried to get a bill filed a couple years ago [moving school starts] closer to Labor Day. It didn't get anywhere.''

Last year's hurricane barrage had some school systems making up for storm-related closings by taking away field trips and days off in the spring. Ross said that cut into attractions' gate receipts, too, with May attendance off 3 percent statewide in the midst of what has otherwise been a strong travel market.

Summer vacation schedules seem to have the most impact on day-camp revenues, Ross said. Attractions and museums often run their own camps every week during the summer, and also charge other camps to visit.

And though the industry isn't claiming a serious shortfall from school starting early, the dollars can add up. At the Miami Children's Museum, summer camp generates 15 percent of the Miami attraction's revenue from June to August, a three-month stretch that accounts for about 42 percent of the museum's annual revenues.

Many camps offer a new theme each week in hopes children will sign up for a large chunk of the summer. Friday marked the end of Fizz Bang Boom week at Fort Lauderdale's Museum of Discovery. Roughly 90 children between the ages of 6 and 12 watched their hair frizz from an electrical generator and made baking soda and vinegar combust.

Enrollment costs $195 a week ($170 for members), roughly the same as the Seaquarium's $185 fee (with discounts for multiple weeks). Like the Discovery Museum, the Seaquarium cut back its regular two weeks of camp in August to one to match the school calendar.

The early start for school this year also meant an early start for summer vacation in June, but the attraction industry says the doldrums of late summer tend to send more campers their way.

Not everyone has the summertime blues, though. Some private schools aren't heading back to school until later in August, leaving those students free to wile away a few more days at camp.

''It really hasn't been that large of an impact, ,'' said Melissa Wagner, marketing director of Young at Art Children's Museum in Davie. ``We actually added an additional week this year for private school students.''