I don't have a kiddo with adhd, but had one who really had trouble focusing and also had trouble with letters (I suspect mild dyslexia but he was never diagnosed with that). I am also a substitute teacher. If you know her learning style (ask teacher about this if you don't) that may help guide you.
Does she have an IEP (individualized education plan)? Some kids with IEPs have a shorter spelling list than the regular list. Would this be a possibility? I can understand if you don't want to go there just yet, but something to think about.
Maybe she would benefit from practicing the words in different ways. Some ideas might be--
using the magnetic letters on the fridge to spell the words
writing them on a dry-erase board with a marker
write them in sand with a stick
put a rectangle of shaving cream on the table and let her write a word with her finger. Re-smooth shaving cream for next word. Bonus--you get a really clean table!
arrange buttons/coins/string/wire/twisty ties/popcorn/dry beans to form the letters
writing them with crayons or markers on a BIG sheet of paper (maybe taped to the wall? watch out that markers don't bleed through)
make cards with one letter on each card, let her arrange them to spell the word
say each letter as she hops, jumps, stamps a foot, claps a hand, goes up a step, etc (gets some of the "wiggles" out, too)
sing the letters
whisper the letters
form the letters with her body (my son LOVED this one--he is a kinesthetic learner--though it was a little hard sometimes to figure out which letter he was forming)
I applaud you for not sharing with her that you hate to read!
Hope this helps a little.
Good luck,and please let us know what happens!
BTW--my kiddo is now 15.5 and on Honor Roll. No longer needs his IEP. Spelling isn't his strong suit but he works around it.
K. Z.