A core concept in constructivist theory is scaffolding, introduced by Jerome Bruner and closely tied to Vygotsky’s idea of the Zone of Proximal Development (ZPD). Scaffolding refers to the temporary support provided by a teacher or peer to help a learner accomplish a task they would not be able to complete independently. As the learner gains competence, the support is gradually removed.

Example: In an ESL classroom, a teacher might first model how to write a simple descriptive paragraph. They provide sentence starters, vocabulary aids, and guide students through each step. As students become more confident, the teacher reduces the help—eventually allowing students to write paragraphs independently.

What is insightful about scaffolding is its student-centered approach, which respects individual differences in learning pace and readiness. It promotes active engagement, where the learner is not just receiving knowledge but building it through interaction and guided discovery. This approach fosters deeper understanding and long-term retention of knowledge.

However, limitations of scaffolding include the assumption that all learners have access to capable mentors or teachers who can provide the right type and amount of support. Moreover, constructivism, in focusing heavily on individual learning paths, may underemphasize systemic factors such as curriculum constraints, standardized testing, and classroom size. There is also the risk of inconsistent application—too much support may hinder independence, while too little may leave the student frustrated.

Despite these challenges, scaffolding remains a powerful tool in constructivist teaching, especially when combined with thoughtful observation and continuous assessment of learners' needs.