Constructivism is a theory of knowledge which asserts that, as individuals and groups interact with each other and with the physical environment, they develop a representation of what they take to be reality. Or, actions may lead to unforeseen or unsatisfactory consequences, in which case the schema is challenged. Of course, postmodernday constructivists do not define constructivism with anything approaching the elegance of the above lines. They do not know how. Experience is a construction.
Experience is constructed with constructs.
Constructs are constructed out of experience. Experience is reality. They just don't know it.