I read “The impact of user interface on young children’s computational thinking” (pdf) by Sullivan, Bers, Pugnali (2017). Wonderful paper!

Authors compare a tangible interface to robotics programming and a non-tangible interface. The tangible interface is KIBO, a robotic kit programmed with wooden blocks, basically making Scratch physical. (I totally love KIBO, so I’m biased ;)

The non-tangible interface is ScratchJr, i.e. robots are programmed via the screen of a tablet.

They compare it with children in the age range 4-7 (average age of 5.86 years old!). Both groups had 14 children. The curriculum for both groups explored the same computational thinking concepts: sequencing, repeat loops, and conditionals.

Results:

1) COMPUTATIONAL THINKING: The evaluation compared the two groups with respect to four computational thinking categories: Sequencing, Repeat Loops, Conditional Statements, and Debugging.
(kibo > scratchjr) Students in the tangible KIBO group scored higher across all four computational thinking categories in comparison to the graphical ScratchJr group. Differences for sequencing and debugging tasks were statistically significant.

2) POSITIVE TECHNOLOGICAL DEVELOPMENT. The evaluation compared the two groups with respect to 6 positive behaviors (6 C): content creation, creativity, communication, collaboration, community building and choices of conduct.

• content creation and creativity:
  (kibo) children in the tangible group focused on the goal at hand first and once, that was complete, they moved onto exploring other ideas. They also explored the different functions within KIBO’s programming language as their main creative outlet instead of focusing on the art materials around them.
  (scratchjr) Those in the graphical group often got distracted by the multitude of options within the application, but eventually completed the challenge given to them. They spent time using the paint editor features that ScratchJr offers to edit and create characters and backgrounds as their way of making their projects stand out from the rest.
• communication and collaboration:
  (kibo) In the tangible group, students were able to easily look around the room and see other student’s robots. This allowed them to explore what everyone was doing and to prompt them to ask one another questions and receive peer help and input on their own work. It also allowed counselors and research assistants to easily see who was on or off task, and to see who needed help.
  (scrtachjr) In contrast, in the graphical group, it was much more difficult for counselors to see what children were working on and whether or not they were off task. It was difficult to see what was on each child’s iPad screen at any given time, meaning that both children and counselors needed to go out of their way to find out what everyone was working on and to ask questions. Finally, it put more responsibility on the child to ask for help, since the adults could not always tell if there were any problems with the kids’ programs.
• choise of conduct and community building (i.e. general ambiance of the room)
  (kibo) In the tangible group, children were often moving around with their robots or going over to other groups to explore their projects. The children were also generally on the louder side, especially when sharing their projects in the tech circle. They seemed very engaged and eager to share their learning.
  (scratchjr) With the graphical group, children were generally very quiet and respectful in the traditional classroom sense. They were often either hyper-focused on their own work, or on the people close to them. Students only occasionally walked around to explore other people’s projects. It was clear from these observations that both groups demonstrated positive conduct and community building, but it different ways.

From my personal subjective preferences, I would say that manipulating things with hands (tangible) is better than manipulating abstract things on a tablet screen. Montessori docet! ;)

Reference: Sullivan, A., Bers, M., & Pugnali, A. (2017). The impact of user interface on young children’s computational thinking. Journal of Information Technology Education: Innovations in Practice, 16(1), 171-193.