We have liked Spelling Workout.
I have been homeschooling for twelve years and we have struggled with spelling all twelve years. We tried Sequential Spelling last year and LOVED it. The boys spelling has improved dramatically with this program.
We use Rod and Staff for my 4th and 2nd graders. I really like it.
All About Spelling really helped my kids tremendously. (After the first 2 weeks, both of them told me to never switch programs again, LOL! I was shocked, I'd never had such a strong reaction to a curriculum choice before!) Here's a review I did several years ago, with a few updates as I went along. My oldest has completed the program, and my dd starts the last level soon.
Hope you find just the right program for you and your kids! Merry :-)
My three are a bit older than yours (13, 11 and 10) We started using Spelling Power. It is easy to use and the book can last for many years. It is the first program we have used that did not get groans and whines with it.
We used SS with little to no improvement in over 1year. We just started Phonetic Zoo this year so I don't know yet as far as testing, but we are loving it.
We use ALL about spelling. we love it! It has helped my kids tremendously with their spelling!