Since that curriculum was new to me, I had also ordered the teacher's manual. That is where I learned that there are some keys to helping a left-handed person learn to write correctly. Essentially, the paper needs to be slanted with the top left corner up and the bottom right down. The right hand should hold the paper still as the child writes. And this is the most important part: anything that the child is copying/solving/answering in writing should be placed to his/her right side. The majority of workbooks and worksheets have the text on the left with room to write on the right side of the column:
This is natural for a right-handed person as one can clearly see both columns at once. But if you are a leftie, the arm will cover the problem or text and the wrist will compensate by making a crook so that both columns can be viewed simultaneously. The manual suggested making an extra copy of the worksheet/workbook to place on the right so that the child can be trained to hold the arm in the correct position.