On a recent warm June morning, I brought my daughter Annabelle, 7 and son Luc, 11, to the Muhlenberg College campus to check out the Muhlenberg Summer Music Theatre (MSMT) world premiere of "Gruff!," a family musical based on the classic tale of "The Three Billy Goats Gruff."

Gruff!" "continues through July 26, Studio Theatre, Trexler Pavilion for Theatre & Dance, 2400 Chew St., Allentown.

Luc and Annabelle are now seasoned Lehigh Valley children's theater-goers, but this was our first time at an MSMT production.

Having arrived early, Annabelle was happy to find that there were "Gruff!"-themed activity books and crayons waiting to help children pass the time in the lobby. Once inside the theater, children were guided to carpeted matts on the stage floor, making them part of the show.

As the rest of the audience was seated, the three Billy Goats (actors wearing goat-horned hats) were already on stage, playing ball and joking with the audience, keeping the young ones from getting antsy as they waited for the show to begin.

The play opened with slapstick comedy and audience participation. Clapping along, singing, yelling and dancing is encouraged throughout the show.

Annabelle and Luc were excited when the Goats made conversation with them and even more excited when the colorful and fluffy Muppet-like Troll puppets joined the Goats onstage.

The puppets bring life to a story of environmental awareness that might otherwise have gotten too preachy for the young audience. Each puppet is handled by one or two actors whose facial expressions and dance-like movements add extra punch to the puppetry.

Environmental awareness is not the only theme explored in "Gruff!," written by Ora Fruchter, who also directed, and Christopher Scheer. Prejudice, stereotypes and tolerance are also examined as the Billy Goats and Trolls must confront their negative feelings towards each other in order to save their world.

Through several adventures and crazy shenanigans, the Trolls and Billy Goats learn to not be afraid of each other. With the planting of a magical glowing seed, they save the land from turning into one giant trash mountain.

With original songs (music by Toby Singer, lyrics by Fruchter), including "Nothing Could Stop Us" and "Game Of A World," the themes are made accessible to the audience.

"Gruff," running approximately one hour with no intermission, keeps children and parents alike entertained.

Luc and Annabelle loved the show. We found MSMT's "Gruff" to be a thoroughly enjoyable way for our family to spend a summer morning.

Show times: 10 a.m., 1 p.m. Wednesday - Friday, 10 a.m. Saturday, through July 26.

Tickets: muhlenberg.edu/SMT, 484-664-3333