The study aimed to assess the effectiveness of the multidimensional curriculum model (MdCM) in the development of higher-order thinking skills in a sample of 394 elementary and secondary school students in Israel. The study employed a quantitative quasi-experimental pre-post design, using a study module based on MdCM, comparing intervention group to control group. Thinking skills were measured using a thinking questionnaire comprising three dimensions: Scientific thinking--focusing on inquiry skills; creative thinking--relating to problem finding and problem-solving; and future thinking--concerning personal and time perspectives. Findings indicate improvement in measured thinking skills in the intervention group by 40% compared to 4% in control group. Most improved skills were future thinking and creative thinking. Differences were detected according to the type of school. It is suggested that when used regularly the MdCM incorporating innovative teaching--learning strategies and embedded thinking tools could improve thinking skills among students from different age groups. General implications for curriculum design are discussed.