Study on the learning of programming concepts in pre-university students

I want to investigate the ability of a group of students to learn programming concepts in one hour.

- The students are grouped by ages: 6 - 17.
- The tasks are divided into concept and type. Each concept has example tasks, to correct code, to copy code and to write code without help.

I measure the number of tasks completed and the time elapsed in each one.

What is the best way to analyze this data? And to represent them?