This paper describes part of a study undertaken to examine the relationship between dispositions to critical thinking, procedural knowledge in science, and formal reasoning. Three tests were administered to 346 grade 7 students at the beginning and at the end of the school year: California Critical Thinking Dispositions Inventory, Group Assessment of Logical Thinking, and Test of Integrated Process Skills II. Results indicated a possible link between scientific thinking and formal thinking but no relationship between critical thinking dispositions and formal thinking or between critical thinking dispositions and procedural knowledge in science. (Contains 7 tables, 2 figures, and 42 references.) (MKR)