This paper discusses the design of materials that utilize embedded computational techniques to demonstrate the capacity to learn, adapt and develop responsive behaviors that are shaped over time. The focus is on materials that develop time-based relationships based on a level of 'experience' they accumulate from long-term interaction with their users and environment. Materials with 'computational experience' are demonstrated with two designs: an interactive rocking chair that utilizes its material properties and computational abilities to manage its own energy production and consumption while providing physical and mental exercises to its user; and an LED-based, reconfigurable display that adjusts its content based on its interaction with its user while monitoring its internal conditions, environmental factors and usage. These examples are used to discuss the design of computational 'styles' for materials that would not only allow them to express signature characteristics embedded in their physical properties and computational behavior but also function as features that would evolve in response to interaction patterns and accumulated experiences. Throughout the paper, behavior-driven material practices are presented and their potential to influence the look, feel and functionalities of products and spaces are discussed.