Who would cheerfully sacrifice several hours of a beautiful springlike Sunday and submit to the rigors of a music test, all for the fun of it?

More than 400 Montgomery County youngsters would. The budding pianists showed up at Montgomery College on a recent Sunday to take this year's Maryland State Music Teachers Association test -- not on the keyboard but on paper.

Prince George's County will hold its test April 21 at Prince George's Community College, and so far 200 pianists have registered, including Elva Martin, 87, who will attempt level five.

None of the entrants even struck a note. This was the solid stuff, the ABCs of music -- music theory, involving musical terminology, note reading, the writing of chords and scales and ear training.

The reward? A certificate of participation. Those who scored 85 to 91 points had their certificates affixed with a red seal, and those who had 92 points or more out of 100, a gold seal. What they also got, said Ann Mitrisin, a Bethesda piano teacher, was "a sense of achievement to spur them on."

Ten volunteer teachers registered the participants, supervised the tests, and graded the papers afterward.

Michael Douma, 9, of Rockville, who has been playing the piano for two years, took a first-level test.

"That was simple," he said later. "I was the fourth to hand in my test." He took only 15 minutes to fill in the blanks on his test sheet. But he did admit that he found identifying key signatures the hardest part.

Kathy Cummins, 8, of Gaithersburg, said with a little embarrassed smile that she found listening to and then identifying five major or minor chords played by a teacher on the piano a bit tough. Beamed her friend Christine Powel, 9, of Laytonsville, "That part was easy, but then my Dad's a piano tuner, so I hear it all the time."

All three are eager to come back next year to try level two.

The difficulty of the test increases with each level. "This was kind of hard," admitted Laura Clark, 16, of Rockville, who has been playing for seven years. She was one of 14 who took level seven. That test included identifying more complicated chords and taking musical dictation for four measures. "But I love classical music, and so I take the tests. Maybe I want to be a music teacher," she said.

Francis Martin, another Bethesda piano teacher, said the reason she strongly encourages her students to take the test is that "musical theory should be studied alongside the practical piano playing. It should be an integrated process."

The Montgomery County Music Teachers' Association has been administering the test for the state association since 1976. Attendance is growing, with 100 more students attending this year than last. The youngest entrant was only 5 years old, and a dozen adults joined in.

More than half the entrants took level one, two or three, of the 10 levels available. Only four tested for level eight, and Mark Thurber, 13, was the only entrant at level 10.

Average score on the tests was 84.7. There were a number of perfect scores in the lower levels, and one at level five.