Only knowledge is not sufficient to make students succeed in the world. Students need to attain 21st century skills like problem-solving, creativity, innovation, metacognition, communication etc. to endure in the modern world. Problem-solving skill is one of the fundamental human cognitive processes. Whenever students face a situation where they do not know the way to complete a task, the problem occurs. Problem-solving is a process, which involves systematic observation and critical thinking to find an appropriate solution or way to reach the desired goal. The framework of problem-solving consisted of two major skills: observation and critical thinking skill. Observation skill refers to collecting data, understanding and interpreting the meaning of the information using all the senses. Critical thinking involves the individual's ability to do the following: conceptualizing, logical reasoning, applying strategy, analytical thinking, decision making and synthesizing to solve any problem.