Improving User Interface of Spreadsheet Functions by Object-Oriented Design

We propose an improved user interface to use spreadsheet functions by adopting object-oriented design. We examine each step of users´ operations under the existing interface, and clarity the reasons why beginners feel it difficult to make use of built-in-functions. Then we construct so called `function wizard´ for numerical objects by classifying numerical and statistical functions at the K-12 level into eight classes. It is expected that our interface will help learners understand function of functions through easy trial-and-error experiences.