Correct spelling, correct punctuation, and simple computation are skills that are improved by practice and repetition. Since she's only in K, I wouldn't worry.
On a side note, I'm really disappointed with the way they have kids writing these days before they've mastered the basics, since they're basically inviting the children to practice doing it the wrong way. There was no such thing as "inventive spelling" when I was a kid... you spelled it right, or you got marked down. And this is why you did simple sentences until you had enough of a spelling vocabulary and grammar background to write more.
