The Book series called Explode the Code are phonics workbooks for grades K-4 that have been best sellers for over 30 years. I have used the books for my son with Dyslexia and have had great results. He is now a sophomore in high school and you would never know he has dyslexia. He reads college level books, has an excellent vocabulary and has no problems with spelling.
There are workbooks available and there is an online version now. You can see it here: Online Explode the Code Demo. If you want to buy a "seat" meaning, a subscription for one student, you can get a discount here: Homeschool Buyers Co-op. One student is $35, two kids is $70. Good for one year.
Sample of the workbooks and more information can be found here: Explode the Code