Behaviorism 

Actually, behaviorism itself is a worldview that operates on a principle of stimulus response. also, behavior is shaped through positive reinforcement or negative reinforcement. Both positive reinforcement and negative reinforcement increase the probability that the antecedent behavior will happen again. In contrast, punishment (both positive and negative) decreases the likelihood that the antecedent behavior will happen again. Positive indicates the application of a stimulus; Negative indicates the withholding of a stimulus. Learning is therefore defined as a change in behavior in the learner.
In many instances, individuals do learn when provided with the appropriate blend of stimuli, rewards, negative reinforcement, and punishments. Especially with small children and simpler tasks, behavioral principles are often effective. 

Constructivism

Constructivism is basically a theory  based on observation and scientific study  about how people learn.In the classroom, the constructivist view of learning can point towards a number of different teaching practices. In the most general sense, it usually means encouraging students to use active techniques (experiments, real-world problem solving) to create more knowledge and then to reflect on and talk about what they are doing and how their understanding is changing. The teacher makes sure she understands the students' preexisting conceptions, and guides the activity to address them and then build on them.