Programming is a unique way of thinking that leads from a given problem to a solution achievable on a computer. This is precisely why learning programming holds such importance today. Simultaneously, it is also challenging, prompting a natural search for ways to facilitate it through the use of various educational tools. Teaching programming will be more successful if educators gain insight into what students know, but also into what they don't, thus understanding the most common misconceptions students hold is essential. Additional hurdles to effective teaching can arise from abstractions, which constitute fundamental programming concepts. This concern is particularly relevant to fifth and sixth-grade elementary school students, as they find themselves in a concrete phase of cognitive development and face difficulties in the early stages of learning abstract programming concepts that are not suitable for their developmental age. These challenges are exacerbated when traditional teaching methods are employed, coupled with exclusively textual programming languages that emphasize syntax over semantics. In order to overcome the aforementioned difficulties, and due to the lack of similar research involving students who have not yet reached the formal stage of cognitive development, a four-phase study was devised. Research results highlighted the most common misconceptions held by students of this age group, which need to be taken into account when planning introductory programming education. The findings also confirmed that the choice of textual programming language for teaching does not influence student success. Furthermore, the obtained results demonstrated that visualization does not impact learning outcomes, while visual programming, in contrast, has a positive effect on the acquisition of all examined fundamental programming concepts among beginner K-12 level programmers. This effect justifies its application in teaching.