The constructivist theory says that individual learners construct mental models to understand the world around them. Ways the instructional strategies correlate with principal of constructivist/constructionist learning theories is by understanding how students learn.
The best way to help students learn is by having students construct their own knowledge instead of having someone construct it for them. Learning is an active process of creating meaning from different experiences. In other words, students will learn best by trying to make sense of something on their own with the teacher as a guide to help them along the way.
The instructional strategies are put in place aligned with the constructivist theory with this understanding, that all sensory input is organized by the person receiving the stimuli, it cannot always be directly transferred from the teacher to the student. This means that a teacher cannot "pour" information into a student's brain and always expect them to process it and apply it correctly later.
With the constructivist theory saying that individual learners construct mental models, i feel the instructional strategies were built on by certain guidelines. It should be recognized that a person's prior knowledge may help or hurt the construction of meaning. People's prior knowledge comes from their past experiences, culture, and their environment. Generally prior knowledge is good, but sometimes misconceptions and wrong information can be a hindrance. Sometimes time must be spent correcting prior knowledge before new learning can occur.