Trying to Unteaching Kunrei Romaji

I have no problem teaching my eikaiwa students Hepburn Romaji from a young age. I tend to combine it with phonics (digraphs and blends) and using those rules when writing words in Japanese. At a young age, I rarely have any problems.

My eikaiwa students in elementary school and some in junior high school seem to have the hardest time. I'm not looking to reinvent the wheel, but I need some advice for students between 4th and 6th grade.

So far I've made flashcards and have tried some writing activities, but I'm out of new ideas that work. I made a Flippity typing activity for my students, but the younger students' typing skills aren't quite there yet. It's fine with my older students, but it goes too fast for my younger students.

by ChickenPaul3745