Should There Be a Three-Strikes Rule Against Pure Discovery Learning?

In many ways, guided discovery appears to offer the
best method for promoting constructivist learning. The
challenge of teaching by guided discovery is to know how
much and what kind of guidance to provide and to know
how to specify the desired outcome of learning. In some
cases, direct instruction can promote the cognitive processing
needed for constructivist learning, but in others, some
mixture of guidance and exploration is needed (Mayer, R., 2004)

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