This is a self-contained 30-lesson course in spelling which is fun to do and conveniently accessible online.
You only need someone to read the words and sentences in each lesson to you for dictation practice. Everything else can be done entirely by yourself with the help of a good dictionary.
For each lesson, you will find many exercises which focus on difficult aspects of spelling such as singular/plural forms, possessive forms, letters/syllables, roots, suffixes/prefixes, double consonants, contractions, etc. Keys to the exercises are provided so that you can check your answers.
It is a good idea to follow the work plan suggested by the site, which schedules you for 5 days of study a week.
Site URL: http://www.splashesfromtheriver.com/spelling/index.htm