National Board of Accreditation, India has become the signatories of the Washington Accord adopting outcome based education guidelines in order to impart the quality education in engineering institutes . Outcome Based education (OBE) requires thorough assessment and evaluation of the students individually, with special focus on the overall development of the students. OBE is based more on student centric learning and less on the role of a faculty or the content part (taught) which requires modifications at grass root level in the University teaching learning scheme. It demands a transition of a lecturer into a facilitator. It also requires a paradigm shift in teaching learning process in engineering education (EE) system as OBE focuses more on development of all the three learning domains, contradictory to the traditional teaching learning process which focuses more on development of the cognitive domain and psychomotor domain only.
According to the World Bank Report, the modern volatile and complex world demands from the engineers the core employability skills like critical thinking, problem solving, creativity and innovation, collaboration skill, communication skill which must be developed and honed during the course tenure so that they could become competent global engineers  .
This paper brings forth the out of box thinking and implementation concept of the OBE for UG program, through activity based students’ engagement, specially designed activity to achieve Programme Educational Outcomes (PEOs), Programme Outcomes (POs) and Course Learning Outcomes (CLOs). It intends to solve the problem of large classes through the implementation of the FLIP classroom model. A six month activity based teaching learning model had been adopted for different streams, involving more than 1500 engineering students. The outcome/s achieved by each activity had been termed as Activity Outcomes (AOs). This paper discusses the problems encountered during the implementation of OBE frame work for large class  in context with Indian environment and also strives to provide some methods to implement activity based learning to achieve desirable outcomes.