DES MOINES, Iowa (AP) — Iowa State Fair officials are defending the timing of the annual event against critics who say it may be time to set an earlier fair schedule to avoid conflicting with increasing numbers of school districts moving up the start of their academic year.

The Des Moines Register reports school districts will begin making decisions this month about their 2015 calendars. Some educators say starting school earlier improves student performance. Several districts already start school during the fair.

The 2015 fair is set for Aug. 13-23. Fair CEO Gary Slater says an early August or July fair could conflict with county fairs. State fair officials say many exhibits like agricultural and horticultural crops, livestock, 4-H and FFA projects are simply not ready to be exhibited.