Hi, great question, I seem to recall our ds' 3rd grade teacher shooting for around 60% right first time trying to spell the words. It gives them something to learn but doesn't make them feel like it's completely uphill. I thought this was a nice amount.
In fact when I brought it up to her, she said this was a good question and immediately moved ds up to harder words, and sent out a general note asking parents to let her know if there were others who weren't coming in around that range so she could adjust their lists as well.
In a lot of other ways she was the BEST.TEACHER.EVER, too.
This year ds is getting a spelling list that is somewhat vocab-focused, which is nice, but so far the words are for sure 'babyish' according to him. Since the teacher seems to have a 'system' for her words with week-long premade packets I am worried it might be more of an issue to move him up...which reminds me, I have an email to send her!
I think you are right, if she is getting most or all words right without having to study at all, then she definitely needs harder words! And probably some focus on vocab wouldn't hurt either, the more formal grammar stuff like diagramming might make the teacher faint away, but you could ask....
