Using unplugged coding activities to promote computational thinking (CT) among secondary learners has become increasing popular. Benefits of using unplugged coding activities involve the cost-effective implementation, the ability to promote computer science concepts and self-efficacy in learning computer programming, and the engaging nature of active learning through collaboration. However, there is insufficient information regarding qualitative investigation on how learners develop their CT skills while working on unplugged coding tasks. This study therefore developed unplugged coding activities using flowcharts for high school students to learn computer science concepts, and to promote their CT skills. The activities consisted of five missions encompassing the concepts of sequence, repetition, input & variable, condition, and loop with condition. The data collection was carried out with 120 high students whose participation was video recorded and observed. A thematic analysis revealed that patterns of CT development started from initially developed, to partially developed and fully developed stages, respectively. The various stages were derived from different abilities to apply the computer science concepts to complete the missions with different expressions of CT skills. In addition, the study proposed a 3S self-directed learning approach for fostering the CT development, composing of self-check (in pairs), self-debug (in pairs), and scaffolding. It is therefore suggested to use the 3S model integrated with the unplugged coding activities for developing CT among high school learners.

Prospective teachers facing the 21st century are expected to have the ability to solve problems with a computer mindset. Problems in learning mathematics also require the concept of computational thinking (CT). However, many still find it challenging to solve this problem. The subjects in this study were twenty-one prospective mathematics teachers who took number theory courses, and then two research samples were selected using the purposive sampling technique. This study uses a qualitative descriptive method to describe the thinking process of prospective teachers in solving Diophantine linear equation problems. The results showed that the first subject's thought process was started by turning the problem into a mathematical symbol, looking for the Largest Common Factor (LCF) with the Euclidean algorithm, decomposition process, and evaluation. The second subject does not turn the problem into symbols and does not step back in the algorithm. The researcher found that teacher candidates who found solutions correctly in their thinking process solved mathematical problem used CT components, including reflective abstraction thinking, algorithmic thinking, decomposition, and evaluation. Further research is needed to develop the CT components from the findings of this study on other materials through learning with a CT approach.

The Think-Pair-Share (TPS) strategy makes the learning environment interactive, lively, collaborative and democratic. It allows students to interact; accept information; develop collaborative discussion skills; refine their thinking; and participate effectively in the classroom. In this study, the researchers investigated the effect of the collaborative discussion strategy (think-pair-share) on developing students' skills in solving engineering mathematical problems. Once we had confirmed the validity and reliability of the tools, we used the quasi-experimental approach. The study sample consisted of 66 students divided into two groups: Namely, an experimental group, which comprised 33 students who studied mathematics using the (think-pair-share) strategy; and a control group, which comprised 33 students who studied in the traditional way. Both groups sat for a pretest and post-test in mathematics. The test results showed that the use of the TPS strategy had a positive effect on developing problem-solving skills compared to the traditional method. In light of these results, the study recommended the use of TPS strategy to improve the skills of students in solving engineering mathematical problems.