This special issue works toward refining the understanding of a construct that has had a name for nearly 30 years and has been used by educators of all stripes for centuries. The introduction lays the groundwork for discussing the issues addressed throughout. Each of the papers address different aspects of a similar problem: How can we conceptualize, design, and assess the effects of scaffolding when it is implemented in a complex classroom system? The first article addresses a core problem in conceptualizing scaffolding: What are the specific goals of scaffolding provided in software tools?...