You can take train till Madurai and hire taxies or use buses from there and go in a sequence till TVC from where you can catch a train back
Madurai-Rameshwaram-Tiruchendur-Kanniyakumari-Suhcindram-Trivandrum if you want to have a pilgrimage tour along the beach- you cna also make a trip to Kodaikkanal and back from Madurai