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Before the sixth grade, children will have acquired knowledge of musical intervals, the piano keyboard, and varopis major and minor keys and notations. Up to the sixth grade, children will have learned about the musical intervals, as well as the various keys and experiences of specific musical qualities. Then in the sixth grade, students are led to realize that these intervals, as well as the keys, have additional sides to them and connections with measurements and numbers. Anyone, even with a relatively poor musical development, but knowing that an octave is made by the tones of a string at half of its length will be able to produce an octave as accurately as it could be done by the keenest musical ear. The scientific facts added to art open new possibilities.