It’s “spring break” time for students at all three of Iowa’s public universities, but travel agents say the cost for students who planned a getaway rose quite a bit this year due to rising gasoline prices.Annette Modlin, a consultant for the “Travel World” agency in West Des Moines, who says many people are still headed south this spring break.Modlin says Cancun and Jamaica are the top “spring break” destinations and reservations filled up fast.While “spring break” time is traditionally associated with college student travel, Modlin has booked alot of family vacations this month.