In Latin America, countries are heterogeneous and each country within it presents differences between rural and urban areas; there are students of high and low socioeconomic levels, there are different cultural levels, and even more there are pronounced differences between rural and urban schools with respect to educational quality [1], [2]. In the Huancavelica region, the majority of students who enter university come from rural educational institutions, with low skills in mathematics, problem solving and teamwork [3], [4].
In recent years, there has been research on the effectiveness of interventions based on educational electronic boards in beginning students of STEM (Science, Technology, Engineering and Mathematics). The use of microcontrollers, programmable toys, educational robots and Arduino board in combination with block programming has been the focus of many studies in STEM teaching and learning. Teaching/learning methods based on these electronic devices have been shown to improve students' academic skills [5]- [7]. With the thinking of experts in problem solving, more than a decade of speech to capture your cognitive essence has resulted in a broad set of skills; teaching beginning students continues to be done through the use of computers, educational robots, educational kids and programming concepts, strengthening students' computational thinking and problem-solving skills [8].
Combining effective pedagogies with educational technologies to introduce computational thinking to beginning students is likely to enhance and inspire creativity and problem-solving, rather than
frustration and discouragement in students [9]. Age-appropriate curriculum and technologies are of key importance; for example, well-designed coding tasks integrated into collaborative, problem-based, and/or thematic curriculum designs can support a wide range of students' thinking abilities [10] [35]. Common computational thinking skills are: abstraction, pattern recognition, decomposition, and algorithmic design [11]- [13]; thus, as concepts, practices and computational perspectives [14] [36] and take greater importance to apply them from the first years of study of the university.
This article designs a hardware prototype with block programming to develop computational thinking skills in beginning engineering students or new entrants to college.
It is essential to define computational thinking in higher education; thus, also the varieties of technologies with block programming that are used to teach programming and develop computational thinking in beginning students of higher education.
Computational thinking is one of the most important technological novelties of scientific thought in recent years; computational thinking is considered so that the disciplines of computation are no longer limited only to the use of computer tools, but allow students to become Researchers and innovators in knowledge discovery; computational thinking, also offers limitless possibilities and ways to solve the problem [24].
Several authors express the importance and benefits of computational thinking in higher education. With regard to computational thinking skills, abstraction and algorithmic thinking stand out in strengthening competencies in reading comprehension and in solving complex problems following algorithmic methods [15]- [19]. In a study, it is pointed out that programming is used to perform mathematical tasks, and can improve the student's understanding in abstract topics and with some complexity in its solution; this implies the use of the computer as a tool to solve problems of this discipline [20]. The use of tools based on block programming and interaction with hardware, generates interest and motivation in students; as well as teamwork and problem solving through abstraction, decomposition and algorithmic thinking skills [3]. Also, It directly relates the development of common skills through creative programming and innovation [21], [22]. Finally, critical thinking is added as a form of reasoning and exchange of ideas prior to solving problems through computational thinking skills [23].
Block-based programming languages have been a popular, low-cost method of teaching programming and computational thinking to students and educators with computer science limitations or beginning students. The use of block-based programming languages has been shown to be successful in developing skills in different areas such as computer science and computational thinking [22] [37]. For example, block-based programs such as Scratch or mBlock [25] allow beginning students to create stories of their city in a given historical period, and in such activities students use skills and knowledge of mathematics, technology, communication and social sciences [16], [26]. The most common programming tools used in beginning students are: Scratch, mBlock and App Inventor; the visual assessment tool is also based on blocks, such as Dr. Scratch [26] [38].
Robot programming has shown benefits in the educational context and also shows value as an aid to building computational thinking skills as well, such as teamwork, problem-solving and creativity skills [27]- [30]. However, in several contexts an important limitation imposed by the educative robots is the cost involved in the acquisition and implementation of these technologies; in addition, a robot can be a complex environment for elementary algorithms, or to solve real problems of society.
The creation of custom hardware prototypes using processor boards (Arduino board and esp8266) helps in the acquisition of abstraction, problem solving and algorithmic thinking skills, and have been proved to be low-cost alternatives and are so illustrative as commercial solutions (educational robotics or other educational technologies) [27].
Various electronic devices (sensors and output devices) have been considered to design a hardware prototype with block-based programming. Through the hardware prototype, the beginning student will develop the 3 dimensions of computational thinking (concepts, practices and computational perspectives).
The hardware prototype design proposal with block programming consists of two main components (hardware and software), as shown in Figure 1 and Table 1. The hardware component is composed of a processor (Arduino board and esp8266), sensors, actuators and a module with connectivity to the IoT (Internet of Things). Sensors and actuators are related to features of the real-world environment around us. The electronic sensors are: ambient temperature and humidity sensor (DHT11), water temperature sensor (DS18B20), crop soil moisture sensor, ambient light sensor (LDR), nearby obstacle detection sensor (HC-SR04-PIR-HC-SR501). The output devices are: display of states and values of environmental parameters (screen OLED-7 segments-LEDs), control of servo motors (SG90), emission of sound for the generation of alerts (buzzer) and sending of data using IoT technology. The software component is made up of a development environment based on the mBlock software [31].
With the development of the hardware prototype with block programming, students recently admitted at university will develop activities or projects in the classroom, following the steps of problem solving: understanding the problem, preparing the plan, executing the plan and reviewing the solution [32] [39]. These activities or projects will be related to the real problems of the students' context; during the execution of the project, the students will develop programs, interact with the sensors and show the results in the output devices; these acquired skills will have an impact on their university training by providing skills in critical thinking and teamwork.
The hardware prototype with block programming in recent students will allow the development of computational thinking skills based on the 3 computational dimensions (Table 2): concepts, practices and computational perspectives [14] [34]. Students will develop technological projects using the prototype; these projects will be related to solving problems in their geographical context; since the prototype will allow to implement different solutions based on electronic sensors; for example, ambient temperature sensor, distance sensor, water temperature sensor, obstacle detection sensor, etc., these solutions will have a graphical interface that will be developed through programming in blocks, such as the mBlock, which will allow interacting with the sensors and verifying the results in the output devices (LEDs, servomotor, buzzer, LED matrix, etc.). The use of a permission-based programming interface will allow students to focus on computational concepts rather than the syntax of programming languages; while the presence of electronic sensors and output devices will allow students to enthusiastically view the actual movement/consequence of the program occurring in the physical world, generating immediate visual feedback from programming, motivating beginning students to more easily test their hypotheses and refine their ideas [9], [33].
This article proposes the design of a hardware prototype with block-based programming, as a technological alternative that will allow the development of computational thinking skills in students recently admitted at university; this prototype will help in the teaching/learning process about computational thinking through the creation of real scenarios (i.e. a hardware object that can be touched and controlled) as a final product that interacts with a graphical interface through block programming. By using electronic components or sensors as a low-cost strategy, students will be able to implement successful solutions to solve real problems in their context. Finally, we also believe that the proposed hardware prototype is a cost-effective solution; our approach can be valuable as an educational resource in economically challenged or poor regions, such as Peru's Huancavelica region; in addition, they can be integrated into course curricula related to programming, experimental methods, information management, and other similar disciplines.