Is there a site for kids K-12 to help with spelling and sentence structure?

Hi Deborah,

I know it's been two years since you asked this question, but since then, Khan Academy has added a Grammar section that your boys might practice:

https://www.khanacademy.org/humanities/grammar

I am looking for the same program. If Khan Academy doesn't offer spelling, I would like a program that does that is similar to it for my elementary age student. Hopefully, Khan will offer spelling soon :) 

I am also looking for spelling / phonics for middle school. Hopefully, Khan is able to add a course for elementary and middle school. 

I am also looking for the same recommendations that is more than the grammar section

I would love for Khan to include a spelling section. It would be a valuable addition to the suite of courses.