In this study, the relationship between the design of written music and the amount of mistakes children with and without dyslexia make in reading music is investigated. Previous research shows that children with dyslexia can have difficulty in reading music, especially regarding reading pitch. Common mistakes are so-called third-transpositions. Based on insights from previous studies, a questionnaire was developed with several designs of written music. The questionnaire was filled out by 72 Dutch children between eight and thirteen years old. The results show that children with dyslexia did make significantly more mistakes in reading pitch than normal-reading children. The amount of mistakes was reduced by enlarging the staves and also by writing the stems of the notes all in the same direction. Using differently coloured lines in the staff did not reduce the amount of mistakes and was in some cases counterproductive.