The cognitive abilities and assessment techniques are two major factors that can affect the learners’ achievement in science and their attitude towards learning science. The science assessment techniques usually contain complicated and abstract concepts that require a great deal of critical thinking and analytical skills on the part of the students. Critical thinking and analytical skills are higher order cognitive skills which need appropriate cognitive development. Therefore, it is needed to analyze the students’ cognitive levels in accordance with Piaget’s age-stage model and Revised Bloom’s Taxonomy; if there is a gap between actual cognitive conceptual frameworks and required higher order cognitive skills for achievement in science, that in turn can affect the students’ attitude towards the learning of science. This study aimed to analyze the required cognitive skills of the 8th and 10th grades General Science examination questions and patterns of actual cognitive conceptual frameworks in accordance with the Revised Bloom’s Taxonomy and Piagets’ conceptual frameworks and attitude towards learning of science. Along with that, this study was also focused on exploring the effect of the gap between the examination questions’ difficulty level and students’ Piagetian conceptual frameworks on science achievement and students’ attitude towards learning science. From 23 districts of Sindh province, two districts (Sukkur & Khairpur) were conveniently selected for data collection. The data were collected from 564 8th and 10th graders of 27 elementary and high schools (N= 564: Male = 308, Female = 256, Urban = 258, Rural = 306, 8th graders = 394, 10th graders =170, Elementary school children =362, High school children =202, Sukkur = 255, Khairpur 309). Revised Bloom’s Taxonomy (RBT) was applied to break down the 8th grade General Science examination viii questions in terms of Piagetian conceptual frameworks. Cognitive Science Achievement Test (CSAT) based on the Revised Bloom’s Taxonomy (RBT) was applied to measure the students’ scores in science. The attitude of the students was measured by Teaching of Science Related Attitudes (TOSRA, Fraser, 1981) a five point Likert scale, whereas the existing Piagetian conceptual frameworks of the students were measured by administering of the Group Assessment of Logical Thinking (GALT) Test. Both research instruments (TOSRA, GALT Test) were translated in Sindhi and Urdu (Regional and national language) and were personally administered by the researcher to ensure the reliability and a high rate of return of data. The gap between cognitive difficulty levels of the 8th grade General Science examination questions and existing Piagetian conceptual frameworks of students in 8th grade was calculated. Later, the effects of this gap (between cognitive difficulty levels of the 8th grade General Science examination questions and existing Piagetian conceptual frameworks of students in 8th grade) on science achievement and attitude towards science learning were examined. It was found that students’ parental profile regarding qualification and profession showed a mixed pattern. The cognitive difficulty levels of General science examination questions of 8th grade were found to be distributed unevenly at different Piagetian conceptual frameworks throughout examination questions. Most of the students were at different sub-stages of the Concrete Operational level and a few were at Early Formal Operational level, and only four students out of 564 were at Mature Formal (IIIB) level. It was further found that male students scored higher on the GALT Test in comparison with the female students. However, there was no significant difference between the scores of eighth graders and tenth grade students on the GALT Test.The students of Tenth Grade performed equally better with the students of eighth grade in district Sukkur. The eighth grade students ix of Khairpur district did not show variation within the group scores on the GALT Test. The students of Sukkur district of eighth graders recorded variations within the group in the GALT Test, urban students performed better than the rural students. It was concluded that the male students reflected a slight higher attitude towards science learning than female students in the overall sample between both grades. Similarly, in Sukkur and Khairpur districts separately, again males had a little bit higher attitude towards science learning than female students. On district basis, the female students of Sukkur showed higher attitude towards the learning of science than the Khairpur district. It was concluded that there exists a gap between students’ reasoning ability and examination question’s difficulty level and, with the increase in quantity of the gap, a decrease in attitude towards science learning occurs. It was recommended that the curriculum development experts and paper setters need to develop a model in terms of Piagetian conceptual frameworks for deciding the nature, level and complexity of the questions while developing science assessment techniques at any grade. It is further recommended that teachers replace the didactic teaching method with the interactive one. The teachers should group students with different reasoning abilities within the class. Teachers should use different teaching techniques to introduce the questions of the science assessment techniques to enhance, encourage and motivate students and to develop their attitude towards science learning.