183 - Into Jerusalem Jesus Rode
It's a good text and a strong melody. People may be shy singing it at first because it's not all Victorian sweetness and light in E-flat. But encourage them. Teach it to the choir during the week. Then on Palm Sunday morning, talk with the congregation before the service begins and sing it through with them. Then when it's time to sing (this makes a perfect gradual hymn), add a few drums and you're away to the races!