Empirical Comparison of Visual to Hybrid Formula Manipulation in Educational Programming Languages for Teenagers

Visual programming environments hold great potential for end-user programming, as they, e.g., aim at diminishing the syntactical burden and enabling a focus on the semantic aspects of coding. Hence, graphical approaches have gained attention in the context of K-12 computer science education. Scratch, as being the prime example, is a visual educational language, where even formulas are composed utilizing Lego-style blocks. However, graphical creation and manipulation of complex and nested formulas can become overly cumbersome. Thus, we propose a hybrid approach employing visual creation and textual representation of formulas. In order to evaluate the method, a usability study has been conducted, comparing Scratch to our mobile programming environment, Pocket Code. The findings, while preliminary, indicate an increased efficiency and effectiveness of the hybrid approach employed in Pocket Code in contrast to a purely visual one in Scratch for teenager users.