Supporting Students' Construction of Scientific Explanations by Fading Scaffolds in Instructional Materials

TLDR

The study aimed to determine whether continuous written scaffolds or fading scaffolds more effectively prepare seventh‑grade students to construct scientific explanations once support is removed. In an eight‑week project‑based chemistry unit, 331 seventh‑grade students received either continuous detailed written support or progressively faded support while an explicit instructional model for explanation was reinforced through each investigation. Results showed significant gains in all explanation components, with the faded‑scaffold group producing stronger reasoning on post‑test items lacking scaffolds, indicating that fading scaffolds better equip students to write explanations without support.

Abstract

Abstract The purpose of this study was to determine whether providing students with continuous written instructional support or fading written instructional support (scaffolds) better prepares students to construct scientific explanations when they are no longer provided with support. This article investigated the influence of scaffolding on 331 seventh-grade students' writing of scientific explanations during an 8-week, project-based chemistry unit in which the construction of scientific explanations is a key learning goal. The unit makes an instructional model for explanation explicit to students through a focal lesson and reinforces that model through subsequent written support for each investigation. Students received 1 of 2 treatments in terms of the type of written support: continuous, involving detailed support for every investigation, or faded, involving less support over time. The analyses showed significant learning gains for students for all components of scientific explanation (i.e., claim, evidence, and reasoning). However, on posttest items lacking scaffolds, the faded group gave stronger explanations in terms of their reasoning compared to the continuous group. Fading written scaffolds better equipped students to write explanations when they were not provided with support.