I have several students who struggle so strongly with reversals that they ALWAYS write in capitals for certain letters, just to avoid making a mistake by going the wrong way on the lowercase letter.
I was inspired by one of my students a few weeks ago. He has an amazing level of intelligence and an incredibly high vocabulary. I created a system of "Left Letters" and "Right Letters" to help the kids understand which direction each letter should be written.
I made this set in both standard printing and D'Nealian so you can choose which version is best for your students depending on your school writing standards. CLICK HERE to get it from my TPT store.
In my classroom, I have the small version of the alphabet taped directly to the top of the desks of students who need it. For the number line, I have one laminated for each student and they tuck it inside their math workbooks for easy reference while they work.