Comprehension monitoring is considered a key issue in current debates on ways to improve children's reading comprehension. However, processes and mechanisms underlying this skill are currently not well understood. This article describes one of the first attempts to study comprehension monitoring using eye-tracking methodology. Students in fifth grade were asked to read sentences for comprehension while also checking whether the meaning of the sentence was generally correct or incorrect. Items required the processing of conjunctive relations between two clauses that were either causally consistent or inconsistent. In addition, the polarity of the relation was varied by replacing the conjunction "because" with "although," creating an additional level of processing difficulty. Inconsistency played a minor role and was dominated by polarity effects that were also modulated by the correctness of the answer. The present task represents an effective tool to study local comprehension monitoring and highlights the importance of conjunctive relations for maintaining textual coherence during reading. (Contains 4 tables, 2 figures, and 1 footnote.)