Use the adjective exultant to describe the triumphant feeling you get when you succeed at something. The kids who win the Little League championship game will be exultant.
The kid who's elected sixth grade president will feel exultant, and so will a singer who's just given the performance of her lifetime. Exultant describes an excitement that's a combination of pride, happiness, and triumph. The word exultant comes from the Latin exsilire, "to leap up," from the prefix ex-, "up or out," plus salire, "to leap." In other words, when you're exultant, you're jumping for joy.