I travel for a living and my company watches my expenses closely. Looking at their travel costs, the costs are close to what normal business travel would be. The 181 airline average around $336 a flight, that is reasonable. Using a limo service does not mean that they are getting a limo, sometimes it is cheaper to get a town car and driver than renting a car and paying for parking.
That being said, the school district needs to be open and explain how and why the money is being spent.