In "That's the Spirit," George Washburn, an 8-year-old grouch, and his sister, who hoards Christmas gifts, discover holidays mean sharing. In "Santa and the Haunted House," four schoolmates end up at a roucous Christmas Eve celebration, hosted by ghosts, bats, vampires, skeletons and witches, all tap dancing to a real disco fever.

This year's vacation-filling children's theater includes two highly imaginative and funny plays, both with the de riguer audience participation and Christmas-mean-more-than-presents messages. Both plays - an Archaesus Productions show at the Kennedy Center and a D.C. Department of Recreation-sponsored musical at Howard University - are free.

The more abitious is "Santa," written, directed and choreographed by Laverne H. Reed, which plays through Saturday at Howard's Ira Aldridge Theater. It is a wild, technicolor, hour-long party that never pauses. At times it threatens to self-destruct with its own vitality and outlandishness, so the moment Super Santa - complete with a red cap and with a Big S on his chest - does a waltz is a welcomed slowdown.

The frenzy starts when the children detour through the woods on the way home. They get lost, and go into their first musical number, "The Forest," which sharply resembles music from "The Wiz," the successful makeover of "the Wizard of Oz." Yet this far-off-off-off Broadway show, produced by D.C. Recreation and Howard's children's Theater, does not suffer by comparsion. The trees and the rest of the young cast dip and bop smoothly to Anthony Booker's music, handling the mass scenes with 44 characters as well as the individual cameos.

Deep in the forest,the sacred and sobbing quartet comes across a haunted house, occupied by Dr. Finklefoot. He keep a strange but easily recognized guest list. all varieties of sports including the Black Knight, Frankestein, Count Dracula, Wolfman, a mummy, a sleepwalker, witches and bats, are dressed to glittering heights by Quay Barnes Truitt, and they do their best to entertain the lost children.

The all-black cast, drawn from the Ellington School for the Arts, Howard University and other local schools, uses church and disco rhythms and flip street talk to tell the offbeat story. The Spirits sound like Sunday-morning with the Southern Rock Steady Baptist Choir, and Gertie, the uninvited witch described as a "mean soul sister," threatens to "turn this party out." But everyone get along, and Santa distribute candy canes and balloons to the audience.

Toning down the commercial glitter of all holidays is the theme of "Spirit." This is a much more intimate production as the five actors and the small members of the audience who are allowed to sit on the stage discuss Thanksgiving, Easter, Valentine's Day, as well as celebrations in other countries. But the main emphasis is on proaches of George and Marietta Washburn. the children in the audience help Marietta correct her selfishness and also play detective by finding the invisible cockatoo, Charlie.

"That's the spirit" is scheduled for two performances, 11:30 a.m. and 2:30 p.m. through Friday at the Kennedy center.

"Santa and the Hauted House," will be performed through Friday at 1 and 4 p.m. at the Ira Aldridge Theater. OnSaturday there will be a slight performance at 1 p.m.