CCTC'21 Detailed Programme

Catrobat Computational Thinking Conference 2021

Online Conference – 24th September 2021 (Friday)


We are happy to announce our two keynote speakers, Jens Mönig (Snap!) 09:30 – 10:30 and Eva Marinus (PH Schwyz) 13:15 – 14:25. Both Keynotes will take place in Room A.


Jens Mönig, Researcher at SAP,  Creator of  Snap!



If Computational Thinking can help demystify technology, who enchanted it in the first place? If sufficiently advanced technology is indistinguishable from magic (Clarke) who is to guarantee there isn’t a demon hiding in my phone? If learning Latin forms your brain cells to think logically why study maths at all? Join Jens for a live-coded field trip through magic in education theory, Renaissance riddles, Roman law, a mysterious people named “Rapophagi”, and how to learn Latin in a day.


KEYNOTE 2: Computational Thinking: Conceptual and Methodological Challenges

Eva Marinus, Schwyz University of Teacher Education



Across the globe consensus is growing that programming and computational thinking (CT) are critical skills for all and that they should be embedded in curricula from primary school onwards. However, up to date there is no consensus on definitions of programming and CT skills, and it also remains unclear how these skills can best be taught. Some researchers restrict CT to algorithmic thinking skills, whereas others define CT much broader including skills such as problem solving and creative thinking. There are even researchers who do not believe that CT is a separate skill. And if it does exist, what are its subskills? How do programming and computational thinking relate to each other? Are they partly overlapping or distinct skills? Every researcher who investigates CT must think about such questions and needs to make and justify conceptual decisions before they start their research and develop or select their CT assessments. In the context of the current CT literature this is not an easy task. At the same time, teachers are faced with the challenge of how to implement the learning goals stated in the new curricula. Programming tasks in educational environments such as Scratch and Catrobat involve the application of a range of problem solving, algorithmic thinking and programming language specific skills. How could we tease apart these skills so that they can be separately practiced, in a sensible order so that children (and teachers) do not get overwhelmed, just like how we teach in more established learning domains like reading and mathematics? How do we test which instruction approaches are most beneficial for the learning outcomes? What kind of assessments do we need?

During this keynote I aim to organise different definitions of computational thinking and to disentangle the different (sub)skills that are involved in learning to computer program. In addition, I will discuss several challenges faced by this relatively young field of research. For example, finding consensus on definitions in a highly interdisciplinary field of research, assessment development, and how to design studies that will inform practitioners how to best teach CT and programming.


This year, we have 3 workshops that run in parallel on Friday 24, from 10:30 – 11:30. First, all workshop leaders and participants will meet in the same ZOOM room (Room A) for a joint introduction. After about 10 minutes, the room will be divided into 3 BreakOut Rooms for the different workshops and participants are invited to choose to attend one of the three workshops.

Session I: Experiencing Computational Thinking in Education

Friday, September 24, 10:30 – 11:30, Room A

Workshop 1: Programming in a Spiral Curriculum from Kindergarten to Sixth grade

Jacqueline Staub, ETH Zurich


Call for participation
Computer science is being introduced as a new school subject around the world and with it programming is being introduced across the spectrum of ages. This creative activity trains algorithmic problem-solving, but it also demands a high degree of precision. By the end of compulsory education, students need to have acquired both technical programming skills and the ability to cope with errors. We present a spiral curriculum with an associated programming environment that enables autonomous programming from kindergarten to grade 6 (12 years old).

Target group
Teachers from kindergarten to sixth grade (5-12 years old), open to other target groups


Workshop 2: ManuCode: Coding & Robotics!

Martin Kandlhofer, Austrian Computer Society (OCG)

Call for participation
The workshop deals with the topic of coding in manufacturing, using an educational robotics approach. It is a virtual taster-course, based on the successfully implemented EIT ManuCode summer school concept ( Participants of this workshop will first be introduced to a virtual robotics simulator, followed by programming mobile robots to find certain production material and transport it to a dedicated assembly area.

Target group
Pupils and teachers of secondary education (2nd stage) but also students are welcome to participate. No prior-knowledge is required.


Workshop 3: Programming with Calliope Mini

Franka Futterlieb, Jørn Alraun, Calliope CC

Call for participation

Programming is one of the central fields of knowledge and action of the present and future – and our students are the ones who will help shape the world of tomorrow with their creativity and problem-solving skills. In this workshop you will get an overview of the many ways in which the Calliope mini can be used in the classroom – in elementary and secondary schools and have the chance to write your first programs.

Target group
Teachers and educators




The abstract will be presented during a 20 minutes presentation and followed by a short panel discussion at the end of each presentation. We have 10 paper presentations in 3 sessions starting in Room B at 10:45 – 12:15, parallel to Room A at 11:30 – 12:30 and in the afternoon in Room B at 11:15 – 16:15.

Session II: Experiencing Computational Thinking in Education

Friday, September 24, 11:30 – 12:30, Room A

Talk 1: Modeling with Scratch in Science Education1

Michael Weigend, WWU Münster 


Using models to represent aspects of physical reality is an essential activity in science and science education. In contrast to special purpose modelling software (like Insight Maker for system dynamics) Scratch offers a rich variety of design options and makes it even possible to articulate misconceptions. Animations made by students often look very special and differ from textbook examples. When shared in a studio on the Scratch website they can initiate interesting discussions about model validity. This contribution discusses five approaches of using computer programming with Scratch in classroom activities:  1) Students create linear story-telling animations to visualize a process like a chemical reaction.  2) Students create simulations that – qualitatively – illustrate the invisible causes of observable natural phenomena (like absorption of water by cellulose). 3) Scientific models, found in textbooks, are used as a basis for Scratch projects. Students, when creating useful interactive programs experience similar intellectual challenges as in solving traditional textbook problems.  4) Scratch-animations simulating physical or chemical systems can be specifically designed to check the validity of given mathematical model. 5) An advanced challenge is to specifically design a simulation (like gas diffusion in a closed system with two phases) that might be a basis for discovering a mathematical model for a physical process (like Henry’s law). 

Talk 2: Game Based Learning: Implementation in School

Justin Edwards, Microsoft Minecraft



Minecraft Education Edition is used by approximately 4m young people from 109 countries each month. It’s popularity makes it a great platform on which to build game based learning. However, one of the real success stories has been the use of block coding to carry out ‘in game’ actions. We’ll explore stories from around the world about coding and young people.

As the Director of Learning Programmes for Microsoft, Minecraft, I have a unique insight into how computer coding and computational thinking is developing on our platform. As a former government curriculum adviser and examinations chief executive I bring a unique narrative of how change can occur.

Session I: The Psychological Foundations of Computational Thinking

Friday, September 24, 10:45 – 12:15, Room B

Talk 1: Latent profiles in computational thinking

Josef Guggemos, University of St. Gallen


Computational Thinking (CT) may be an important 21st-century skill. However, due to its multifaceted nature, it is unlikely to observe one overarching computational thinking profile. Rather, students might be assumed to have specific strengths and weaknesses. Hence, a latent profile analysis as a person-centered approach of assessment could yield valuable insights with implications for theory and practice. In the present study, we utilize the Computational Thinking Scales (CTS), an internationally accepted self-assessment instrument, to identify latent CT profiles. CTS comprises five CT dimensions: creativity, algorithmic thinking, cooperativity, critical thinking, and problem solving. Relying on a sample of 202 high-school students from German-speaking Switzerland, we identified four latent profiles. Two of these may be of particular interest. One profile includes students with, on the one hand, moderate to high creative thinking ability, cooperativity, and critical thinking skills and, on the other hand, low algorithmic thinking ability. The second remarkable profile consists of students with particularly low cooperativity. We validate the findings by examining the relationship between the latent profile membership and scores on the Computational Thinking test (CTt), an internationally accepted performance test. Indeed, students in the two remarkable CT profiles differ significantly in their CTt performance. 

Talk 2: The Cognition of Programming: Which Cognitive Skills Predict Programming Performance following a University Computing Course?

Irene Graafsma, University of Groningen

Co-Authors: Serje Robidoux, Lyndsey Nickels, Matthew Roberts, Vince Polito, Judy Zhu, Eva Marinus



There has been a growing interest in teaching students computer programming to prepare them for the demands of our increasingly digital society. Although teaching of programming has commenced across the globe, knowledge of the cognitive skills that underlie programming is still limited. As a result, we lack critical understanding of how programming skills can best be taught. As part of my PhD we examined which cognitive skills are important when learning computer programming for the first time at a university level. We assessed five cognitive skills (pattern recognition, algebra, logical reasoning, grammar learning and vocabulary learning) in 282 students at the start of an undergraduate introductory programming course. At the end of the 12-week course we examined predictors of both their course-related programming performance and their generalised programming performance. Our results suggest that algorithmic/mathematical skills, in particular algebra and logical reasoning, are most relevant when predicting generalised programming success, but also show a role for memory-related language skills.

Talk 3: Keeping computations in mind: How working memory contributes to computational thinking

Ferenc Kemény, University of Graz

Co-Authors: Sabrina Finke, Bernadette Spieler, Bernd Binder, Karin Landerl



The use of computers is inevitable. Individuals use information processing devices on a daily basis: computers, laptops, smartphones, etc. Such usage could vary from simple chatting to automation. One of the crucial questions in computer science education is how different domain-general cognitive abilities support the computational skills. The current presentation analyses the role of short-term and working memory processes. We provide convergent evidence from three different studies highlighting the role of short-term memory and working memory in coding, programming abilities and computational thinking.

In Study 1, primary school children (N=21) were exposed to a coding task in which a continuous event had to be coded into discreet, predefined steps. Children had to solve a maze with a finite number of operators. The best predictor of coding performance was Working Memory Updating on the N-back task, explaining over 23% of the variance.

In Study 2, we investigated how programming naive children learn a visual programming language (PocketCode) on smartphones. Children (N=38) participated in a four-day programming workshop, at the end of which they had to design their own gaming apps. The structure of their final projects was analysed and correlated with measures of short-term memory, arithmetic abilities and creativity. Results showed that short-term memory predicted the number of design elements (how the app is structured in general). Creativity appeared to be beneficial in the mechanics, dynamics and aesthetics of the app. Finally, arithmetic skills correlated with the overall complexity of the app.

Study 3 was aimed at exploring how computational thinking skill – as measured by sample items of the Biber challenge – are predicted by working- and short-term memory skills. Primary school children were recruited from grade 4 (aged 9-11, N = 73). Results showed that verbal short-term memory was the only significant contributor, verbal working memory and visuospatial memory were not.

Overall, converging evidence demonstrates the highlighted role of short-term and working memory skills in computational thinking and programming in primary school children.

Different domains of computational thinking, however, were supported by different short-term and working-memory processes.

Session II: The Psychological Foundations of Computational Thinking

Friday, September 24, 14:15 – 16:15, Room B

Talk 4: Numerical foundations of computational thinking: The roles of mental arithmetic and arithmetic problem-solving

Sabrina Finke, University of Graz

Co-Authors: Ferenc Kemény, Karin Landerl



What are the cognitive mechanisms supporting Computational Thinking (CT)? While previous research highlighted the contribution of fluid reasoning and spatial abilities, evidence on the contribution of mathematical abilities is still inconclusive. To advance our theoretical understanding of the cognitive foundations of CT, it is important to disentangle between different numerical skills, as these should not be viewed as monolithic traits. In an ongoing research project, we thus aim to unravel the unique relations between CT and numerical reasoning, mental calculations, and arithmetic problem-solving in students from Grades 7 and 8. Participants complete a battery of psychometric assessments of CT, numerical and spatial abilities, as well as reasoning. Preliminary results point to a relevant contribution of quantitative knowledge (i.e., mental calculations and arithmetic problem-solving) to CT, whereas the relation with numerical reasoning is less pronounced. Thus, numeracy – and particularly, school-related mathematical achievement – should not be underestimated when aiming to promote CT skills for all.

Talk 5: The Computerized Adaptive Programming Concepts Test (CAPCT) – Designing, Testing, and Practical Implications

Sally Hogenboom, University of Amsterdam

Co-Authors: Felienne F. J. Hermans, Han L. J. van der Maas


We present a new measurement of programming concept comprehension: the Computerized Adaptive Programming Concepts Test (CAPCT). We used the online adaptive environment Math Garden to internally validate a set of 4486 items. The CAPCT measures understanding of basic sequences, loops, conditions (if & if-else statements), debugging, multiple agents, procedures, and the ability to generalize to a new syntax. We will discuss the design principles behind each item type, including the selection of common misconceptions as distractor answer options. More than 90,000 children (4 – 13) provided approximately 19 million responses – allowing us to internally validate the items, explore differences between programming concepts, and estimate predictors of ability. We will conclude our talk by discussing avenues for future research and the potential for practical use of the CAPCT in education.

Talk 6: Cognitive Correlates of computational thinking in primary school students

Authors: Manuel Ninaus (Department of Psychology, University of Innsbruck, Innsbruck, Austria)

Co-Authors: Katerina Tsarava, Korbinian Moeller


A commonly accepted cognitive definition of computational thinking (CT) is still missing. However, this is crucial for evaluating instructional material and establishing a reliable assessment of CT. Studies on the cognitive foundation of CT in primary school students are particularly scarce. Thus, the current study assessed computational thinking using an adapted version of the validated CT test and a range of cognitive skills in 192 3rd and 4th graders. Besides overall satisfactory reliability on our adapted CT test, we identified positive associations between CT and verbal reasoning abilities, non-verbal visuospatial abilities, and complex numerical abilities. We compared these results with other studies of the same age group as well as with older populations. These comparisons revealed a differential pattern across age groups. Theoretical and practical implications are discussed.


Talk 7: Techniques for solving complex problems in computer science

Bernadette Spieler, Zurich University of Teacher Education



There is a growing interest in teaching students programming to prepare them for the demands of our increasingly digital society. Computational thinking (CT) and programming are often referred to as the literacy of the 21st century. The consensus is growing that CT and programming are critical skills that everyone needs and are rapidly becoming a new domain of learning, on par with reading and mathematics. However, a critical approach to new technologies requires a general understanding of the logical and technical aspects behind them. So far, European school systems are mainly concerned with digital literacy and information and communication technology (ICT) as a supportive, context-free medium/technology to enhance learning. According to J. Wing, CT “represents a universally applicable attitude and skill set everyone, not just computer scientists, would be eager to learn and use.”. Under certain conditions, coding activities are one way to practice CT. In addition to coding, CT represents various techniques for solving complex problems. These include decomposition, pattern recognition, abstraction, and algorithmic design, as well as creativity or communication. These competencies can be applied across disciplines and integrated in different subjects. In response to the demand for more IT professionals and a future society that is digitally literate, we have seen changes in education internationally, including the introduction of new mandatory subjects and courses. For example, the “Lehrplan 21” in Switzerland or the “Digital Basic Education” in Austria. On the one hand, integrating a new subject requires flexibility, as teachers are confused not only about the structure of the content, but also about how to teach such new content or tools. On the other hand, there is a great heterogeneity not only among students but also among teachers, as many have to teach this knowledge without a required training. Another serious problem arises from the gender disparity in technology-related fields. In general, the percentage of women in STEM (Science, Technology, Engineering, Mathematics). Because most teens acquire only “low-level” knowledge in CS during their school years, they often have misleading preconceptions about the basic ideas of CS and stereotype-based expectations. As a result, many teens exclude computer science from their career path and CS remains a major unknown. This presentation introduces different approaches to train CT (e.g., CS unplugged, Bebra’s Challenges, visual coding tools such as Pocket Code) to show the possibilities of CT-activities and how those can be integrated into school curricula as well as across disciplines.


Session III: Experiencing Computational Thinking in Education


Friday, September 24, 14:15 – 15:15, Room A

Der Begriff «Making» umfasst vielseitige Tätigkeiten rund um ein kreatives und digitales Gestalten und fördert gleichzeitig wichtige Fähigkeiten wie Zusammenarbeit, Problemlösung, digitale Kompetenz oder auch Computational Thinking. Während es in informellen Lernumgebungen bereits viele Angebote rund um Making gibt, hat sich Making in der formalen Bildung noch nicht durchgesetzt. In dieser Podiumsdiskussion kommen 3 Lehrer:innen aus Österreich, Deutschland und der Schweiz zusammen um ihre Erfahrungen und Best-Practice Beispiele zu Making austauschen! Sie gehen der spannenden Fragen nach, wie Making in den Lehrplänen der einzelnen Länder/Bundesländer/Kantone im DACH-Bereich umgesetzt werden kann. Gibt es Handlungsempfehlungen, wo sehen sie Chancen oder gar Einschränkungen? Alle, die sich für Making interessieren, sind herzlich eingeladen, an der Podiumsdiskussion teilzunehmen.

Bettina Waldvogel

PH Schaffenhausen (Schweiz)

Dr. Bettina Waldvogel studierte Informatik an der ETH Zürich und doktorierte in Umweltnaturwissenschaften. Sie absolvierte das höhere Lehramt in Informatik sowie eine Ausbildung zur Primarlehrerin. Sie forscht im Bereich Förderung von Informatikkompetenzen bei Kindern. Sie ist Fachbereichsleiterin Medien und Informatik an der Pädagogischen Hochschule Schaffhausen und arbeitet als Dozentin und in der Forschung.

Aktuelle Projekte

Projekte und Schwerpunkte in der Arbeit und Forschung: Weiterbildungskurse in E-Textilien und Paper Circuits für Lehrpersonen der Primar- und Sekundarschule.
Erfahrungen mit einem «Makerspace-Light» in einer Primarschule. Erforschung der Präkonzepte zur Informatik bei Primarschulkindern. Förderung von Informatik-Kompetenzen im Kindergarten.   

Mirek Hancl

LeG Uelzen (Deutschland)

Mirek Hančl unterrichtet Chemie und Informatik am Lessing-Gymnasium in Uelzen. Er ist Autor zahlreicher Fachartikel und freier Unterrichtsmaterialien. Seine Arbeitsschwerpunkte liegen in den Bereichen Schulinformatik, Maker Education, AR/VR, Spielebasiertes Lernen und Connected Learning. Hančl hat einige seiner

Unterrichtsprojekte auf veröffentlicht und ist auf Twitter und YouTube als @infchem unterwegs.


Aktuelle Projekte

Interaktive Lapbooks: hybride Coding&Making-Artefakte im Unterricht


Ein klassisches Lapbook enthält bewegliche Elemente wie Aufklappkarten und Leporellos, in denen verschiedene Inhalte zu einem Unterrichtsthema zu entdecken sind. Lapbooks werden von den Schüler:innen individuell erstellt, der Schwerpunkt des Unterrichtsgeschehens liegt dabei auf dem Prozess des Machens selbst und nicht allein auf dem fertigen Produkt. Durch die Einbindung von Elementen wie Stromkreisen, Microcontrollern, AR-Bildmarkern und QR-Codes, die zu Scratch-Projekten führen, entsteht so aus dem klassischen Lapbook ein hybrides Coding&Making-Artefakt.

Das Bildungsnetzwerk Technik Österreich hat sich zum Ziel gesetzt die Bildungslandschaft in Österreich mit modernen Technologien und Methoden an die Anforderungen kommender Generationen anzupassen und hier speziell auch auf Mädchen einzugehen. Die Klimakrise, Herausforderungen der Automatisierung und Künstliche Intelligenz sind Themen auf die Schule und informelle Bildungseinrichtungen vorbereiten müssen. Gerade in den Bereichen der Maker Education und des Informatischen Denkens (Computational Thinking) werden in den kommenden Jahren zielgerichtete Progamme für Lehrer*innen und Schulen angeboten.

Nanna Sagbauer

HTL Hollabrunn (Österreich)

Aus Energie- und Elektrotechnik kommend, was sie auch an einer berufsbildenden höheren Schule unterrichtet, erforscht Nanna Sagbauer in ihrer wissenschaftlichen Arbeit Makerspaces und Makereducation mit speziellem Fokus auf sekundäre Bildungseinrichtungen. Der Aufbau und die Leitung des Makerspace an der HTL Hollabrunn in Niederösterreich ermöglichen ihr eine enge Verzahnung von Wissenschaft und Praxis im täglichen Schulalltag. Beim Bildungsnetzwerk Technik Österreich hat sie 2021 den Vorsitz übernommen um ihr Wissen weiterzugeben.

Michael Pollak 

“Bildungsetzwerk Technik Österreich” (Österreich)

In seiner wissenschaftlichen Arbeit beschäftigt sich Michael Pollak mit der problematisch kleinen Schnittmenge zwischen aktuellen technologischen Möglichkeiten und den Angeboten an Schülerinnen und Schüler.

Durch die Integration von Praktikerinnen und Praktikern aus der Wirtschaft mit einem Fokus auf das Unternehmer*innentum versucht er diese Lücke nachhaltig zu schliessen indem er Schnittstellen zwischen interessierten Schulen und technikaffinen Menschen gestaltet.


Demos are being presented on Friday, September 24 15:15 – 16:16. Same principle as for workshops: all presenters and participants will meet in the same ZOOM room (Room A) for a joint introduction. After about 10 minutes, the room will be divided into 3 BreakOut Rooms for the different demos and participants are invited to choose to attend one of the three workshops.

Session IV: Experiencing Computational Thinking in Education

Friday, September 24 15:15 – 16:16, Room A

Demo 1: Cybersicherheit - spielerischer Unterrichtsansatz

Verena Buder, Graz University of Technology 

(in German)

Mach mit

In der heutigen technologiegeprägten Welt, sollte Wissen über Cybersicherheit nicht länger ein beiläufiges und unpopuläres Thema sein, sondern einen festen Bestandteil des Grundlagenwissens bilden und das Interesse der Schüler und Schülerinnen wecken. In diesem Sinne haben wir das Thema mit der Anwendung Pocket Code auf spielerische Weise aufbereitet und einen entsprechenden Lehrplan erstellt. Die Demo gibt einen Einblick in das dabei entstandene Projekt “Security Land” und dessen Einsatz im Unterricht.

Lehrer:innen ab Klasse 5 (Kinder ab 10 Jahren), unterstützendes Lernmaterial für Lehrer:innen


Demo 2: KOALA - Online-Plattform zum Erlernen von Programmiersprachen

David Andrews, bits4kids

(in German)

Mach mit

Unsere KOALA-Online-Lernplattform soll den Einstieg in das Programmieren noch einfacher machen. Wir verfolgen einen konstructionistischen Ansatz, bei dem Spaß und kreative Formen des Lernens im Vordergrund stehen. Du kannst entweder in deinem eigenen Tempo auf der KOALA-Plattform lernen oder einem unserer von Trainer:innen geleiteten Online-Coding-Clubs (OCC) beitreten. Des Weiteren ist ein Austausch mit Gleichgesinnten auf dem bits4kids Discord Server möglich, sowie Fragen stellen und vernetzen. Die Kombination dieser drei Tools (KOALA, OCC, Discord) soll ein niedrigschwelliges und lernerzentriertes Online-Lernen garantieren.


Lehrkräfte für Kinder von 8 bis 15 Jahren


Demo 3: Computational Thinking and CATROBAT

Wolfgang Slany, Catrobat Team

(in English)


Call for participation

Pocket Code is a visual programming language environment that allows the creation of games, stories, animations, and many types of other apps directly on phones or tablets, thereby teaching fundamental programming skills. Drag and drop interfaces particularly make a lot of sense on smartphones, as users prefer using their fingers for dragging and dropping graphical elements on the multi-touch screen in almost all apps, even when entering text on “swipe”-type keyboards. In this workshop we will show you how to create small games easily with Pocket Code.

Target group

Teachers, researchers and all those interested in developing their own games

Video teaser