Jana, you're correct in stating that using the abacus is different than using a calculator. This is because when using the abacus your daughter "sees" the quantities and how they relate to each other. I think she is doing very well to be getting some of the questions asked solved mentally. Do not hesitate to let her use the calculator. Let he use it now so later she won't need too. By using the abacus she is setting in her mind the ability to visualize and see the abacus in her head later.

I hope this helps. Feel free to email any more questions you might have.

Sincerely, Rosine