I taught Punnett squares with brailled squares or dark lined large squares on a whole sheet of paper with binder clips to represent the dominant and recessive traits. I set the clips above and beside the paper on the top and side and discussed that these were the parents. Then I demonstrated with the students (sometimes hand over hand) how we can figure out what the offspring would be in each square and talked about the percentages. Once the student understood the basics I moved them to a brailled Punnett square and introduced uppercase and lowercase letters to represent the dominant and recessive traits. I used a larger Punnett square (16 squares) for two traits. This method of using the large and small binder clips does not work for all students; some understood it better just using the upper and lowercase letters.
To make simple 4-square Punnett squares, the braille student can simply fold a piece of braille paper twice and write the parent traits at the top and on the leftmost side of the squares.
