I work with math professors and have received conflicting thoughts about calculators. Some like students to do as much as possible in their heads while others like to save time on basic calculations while focusing on new material. It's good to learn to use a calculator well (including graphing and functions), but that's a separate issue.
Personally, I want my daughter to do all standard calculations in her head, saving the calculator for more complex work (complex square roots, logs, etc.). I just think it promotes fluency with mental calculations, although I have nothing with which to back that up. We'll use calculators only for more complex problems and for learning to use the calculator.
It doesn't really matter to me when she first uses it, just how she uses it.
