This study analyzed the widespread distance teaching/learning impact in the context of the COVID-19 pandemic and assessed distance teaching/learning’s effects on students’ intelligence. The distance teaching/learning impact results were evaluated based on the extensive sample tests conducted by applying the Wechsler Abbreviated Scale of Intelligence (WASI) methodology. The tests conducted in January–September 2022 were compared with those conducted in the same age groups in 2017, 2018, 2019, and 2021. The research data were processed in the following three stages: Stage I. Overview of the general situation of the research data concerning the variables. The descriptive statistics method was applied when calculating the percentages representing the students’ verbal, non-verbal, and general IQ. Stage II. Estimation of the statistically significant differences between the independent variables. Stage III. Review of the research data. The descriptive statistics method was applied, and the WASI methodology was used to assess the effects of distance teaching/learning on the IQ of 1–12-grade students in the 2017–2019 and 2021–2022 periods. The test sample size was over 2000 respondents who engaged in the study questionnaires and surveys. The effects of distance teaching/learning were assessed in many relevant aspects to identify which factors considerably impacted students’ intelligence during distance teaching/learning. Also, a more extensive analysis of these factors was performed to reveal which of them, during the period of distance teaching/learning, (1) greatly influenced students’ verbal IQ, (2) significantly impacted students’ non-verbal IQ, and (3) had a substantial impact on students’ general IQ. The results of the 2021 tests, conducted after the announcement of the official end of distance teaching/learning due to the pandemic, showed that distance teaching/learning affected students’ IQ positively. Such results can be associated with an increased number of self-study independent tasks, which in turn influenced the growth of creativity. The IQ tests of students born in 2009 revealed that the total IQ of test participants gradually decreased in 2018, 2019, 2021, and 2022 respectively. These results might have been influenced by the then-prevalent education system, favoring educational programs that do not promote IQ development. It is believed that the parents of children born in Lithuania in 2009 were provided more favorable conditions for raising children than the EU standards. Notably, the IQ of students of aged 6–15 tended to grow from 2017 to 2021, but in 2022, a dramatic drop was observed. The restricted socialization and deficiency of live communication could pose one of the primary reasons for the drop in their IQ. The analysis also showed that distance teaching/learning negatively affected all student groups by age. Age groups differed to a positive and negative extent; e.g., during the research, the most considerable negative effect in the student group aged 6–10 years and the uniqueness of students born in 2009, i.e., the overall highest average IQ of students born that year (134 in 2018), were noticed. However, during the five years afterward, students’ IQs decreased (119 in 2022). The analysis of the socio-economic environment allowed for determining a positive trend that could have been influenced by the most favorable program for families established by the government at that time. Furthermore, the study concluded that distance learning had an apparent adverse effect on the IQ of individuals in the 6–19 age group.