MYA students in Symphony Orchestra are starting rehearsals today on Holst's The Planetsfor a May 24 performance at Ravinia. The performance will be sure to please the thousands of students who will attend this concert which is part of Ravinia's Reach*Teach*Play program. This popular orchestra suite of seven movements is intended to convey ideas and emotions associated with the influence of the planets on the psyche. The composer did not count it among his best creations. He was, however, partial to his own favorite movement, Saturn. Pluto was discovered in 1930, four years before Holst's death, but he had no interested in writing a movement for the new planet. He became disillusioned by the popularity of the piece believing that it took too much attention away from his other works.