Constructivism, perhaps the first well-developed theory of learning, is both a minimalist and an optimalist method of viewing learning. Constructivism de-emphasizes instruction and focuses on giving children methods to actively learn through discovery; it is thus a learner-centered theory as opposed to an instructor-centered theory. The main concept behind this theory is that learners will better retain the information they learn if that information was learned through discovery and experimentation, rather than through instruction. This theory is a broad one, encompassing the work of many early 20th century psychologists, such as Len Vygotsky and Jean Piaget.
Behaviorism is the theory stemming from the belief that learning is achieved through strict control of the objectives and environment of the learning. This theory, based on B.F. Skinner's research on animals in the 1930s, states that instructors take the role of providing the stimuli and objectives for the learner in a way that elicits from the learner the desired responses. Behaviorism has the special feature of disregarding the learner's mental states and processes, whatever they may be.
Cognitivism as a learning theory derives its inspiration from the computer. The learning theory of cognitivism states that the human mind is much like that of a computer: there are inputs that the brain processes and outputs that the brain decides through a type of algorithmic process. The learning that goes on in a cognitive classroom involves an instructor presenting models and ideas in a way that transmits the data to the learner's brain, helping the learner creative schemas for the world around him. The basis for this theory of learning is often attributed to the studies performed by Graham Hitch and Alan Baddeley, two psychologists studying theories of memory in the 1970s.
Humanism as a learning theory is a break from the belief that the human mind is driven by sets of algorithms and information processing. Humanism also goes against the theory of behaviorism, stating that the human mind is not merely conditioned by external stimuli. This newer theory, states that human learning is the ability to make decisions that lead to self-growth. While the roots of humanism are in ancient times, stemming from the ideas of Aristotle and Confucius among others, modern psychologists such as Carl Rogers and Abraham Maslow have promoting this theory of learning as one that sees humankind as intrinsically good and seeking advancement. From the mid-1970s, these psychologists began to influence educators to attach more importance to the encouragement of students in terms of self-growth and self-efficacy.