Doctor of Philosophy (Ph.D.)

It is a common observation that students may not understand what they are doing in the laboratory even if they are competent in the practical skills. While the teaching and learning of science in Singapore schools have always been effective, like most school systems, having a class size of around 40 students may be a challenge for the teacher to help every student master and understand the skills learnt. There is scarce research and practice information on how students learn science practical skills while performing practical tasks in school. The ability to perform science practical skills appropriately is critical in science experiments, especially in research and development. Mastering these skills is also an essential assessment requirement in the secondary science curriculum. This study looks at scaffolding as a potential pedagogical approach to effectively help students master and understand science practical skills, especially those assessed in the science curriculum.

This study examines how Secondary 3-4 school students (Grades 9-10, N=136), working on experiments in a “Scaffolded Chemistry Laboratory” (or SCL), learn and understand the skills acquired in a school laboratory. The SCL resources used consist of 12 chemistry laboratory tasks done over the 2-year chemistry curriculum. Various types of scaffolds were integrated into the chemistry laboratory to support the mastering and learning of practical skills. Chemistry practical tests were used to assess the performance of practical skills after a full school-year (12 months) exposure to SCL.

This is a quasi-experimental study because the participating students all come from intact classes from several different secondary schools in Singapore. The students worked in a SCL environment where multiple scaffolds were provided. However, only one school participated in the Main Study from 2008-2012 and the results obtained from the non-scaffolded Control Class (in 2008-2009) are then compared to those from the three Experimental classes in the same school. These are analysed both quantitatively and qualitatively to probe the effectiveness of distributed scaffolds used in the SCL.

In the Main Study the “non-scaffolded” class and the “scaffolded” classes carried out the same 12 chemistry experiments over a 12-month period, where the scaffolds were gradually removed or faded away (fading is a key feature in scaffolding). Results show that the use of scaffolds in practical work has important implications on student learning of science practical skills in the chemistry laboratory. The findings have provided evidence that the different types of support did help students improve their performance in chemistry laboratory tasks. These supports would be especially helpful in large classes where the teacher may not be able to effectively provide individual attention to all students. Also, by providing different multiple scaffolds in the chemistry laboratory, students’ learning of practical skills can be better enhanced because students have indicated that the scaffolds were helpful in their learning process. Hence, it is recommended that the “scaffolding laboratory” strategy could be encouraged in chemistry practical work to help students in the learning of science practical skills.