Recent studies in museum education focus on the quality of visitor experience to help engagement. To understand how it occurs when it comes to dealing with young visitors to modern art museums, the researchers studied the esthetic experience of Mark Rothko's masterpiece Untitled (1969) with 678 primary and 335 secondary students. Four dimensions--sensory, emotional, cognitive, and spiritual, are taken into consideration for the development and preliminary validation of a specific instrument to evaluate the so-called "Rothko experience." Based on quantitative data analysis, results suggest that school visitors can experience Mark Rothko's modern art intensely by perceiving changes in its color and other sensory features while making self-references to time and space vanish. Besides, cultural background makes a difference in intensely experiencing Rothko's modern art. Suggestions are made for the development of pedagogical strategies that engage young audience in museum experience of modern art.