Fast paced and colorful, the Pennsylvania Playhouse production of ''Schoolhouse Rock Live! Jr.'' combines a cast of fresh-faced kids with catchy songs designed to teach students about grammar, math, science and history.

The simple but fun show is the company's first fully staged student production. A cast of 16 children ages 9 to 16 give an enthusiastic take to the iconic songs from the Saturday morning cartoon series from the 1970s and 1980s.

The 45-minute show, an abridged version of the hit off-Broadway show adapted for young actors, moves quickly as directed by Wendy Borst. It is a perfect length for wiggly youngsters.

The revue-like play features 11 of the TV show's most memorable songs, including ''I'm Just a Bill,'' in which soloist Sawyer Long does a good job bringing to mind the original vocals of Jack Sheldon from the series.

The simple set brings the performers through a giant television screen and into the living room of a teacher played by adult actor Hunter Chadeayne. The only adult in the cast, Chadeayne has energy to spare and holds his own on a stage full of children.

The young actors skillfully change hats and props to fit the scene, depicting lots of characters, from the Statue of Liberty to a crowd of immigrants.

For the song ''Elbow Room,'' about the expansion of the United States, the kids tangle themselves together to humorously demonstrate the overcrowded condition that led to the growth of the country.

One of the show's most memorable songs, ''Interplanet Janet,'' includes lots of on-stage action with Alyssa Reese as Janet in-line skating among the nine planets in the solar system, represented by the other children. Clever sight gags abound, including one student who hula-hoops to represent Saturn.

Richard Rakmahnin does an admirable job cramming in all the words as the lead on ''Conjunction Junction,'' as a trio of girls croons the familiar refrain.

The students' voices blend well on the songs, although some of the younger solo voices are not yet strong enough to completely overcome the lack of amplification in the playhouse's intimate theater. So they can be a little hard to hear.

The Saturday matinee performance also had a special guest, acclaimed jazz pianist Bob Dorough, a Pocono Mountains resident who wrote two of the songs in the show -- ''Three is a Magic Number'' and ''Conjunction Junction.'' Dorough joined the students on stage for a couple of songs after the show.