This article discusses the essence of the PISA international assessment program, its integration with natural sciences, in particular chemistry, and its role in assessing students' functional literacy. The article examines the main directions of PISA tests, their impact on the educational process, and ways to form such competencies as scientific thinking, analytical thinking, and decision-making in problem situations in students through the use of these tests in teaching chemistry. It also presents approaches to assessing chemistry lessons based on modern requirements using sample questions in the PISA format.