Previously, the learning achievements in Chemistry of grade 11 students at Ramwittaya Rachamunklapisek
School in Surin Province of Thailand had been lower than the school standard proposed at 2.50. Also, the students’
integrated science process skills were at a low level due to few opportunities to experience science inquiry
experiments. One of the major topics in Chemistry for grade 11 students is chemical reaction rates. Many students
complained that the topic was difficult as it involved many intangible concepts and required some calculation
(Yasukham, Supasorn & Wongkhan, 2011). The goal of the school was to obtain an Ordinary National Educational
Test (O-NET) score higher than that of Surin Province. O-NET of Thailand revealed that the Science subject score
in Chemistry (Matters and Properties) for high school students at Ramwittaya Rachamunklapisek School from 2009
to 2010 had been lower than the average provincial and national scores, see Table 1 (NIETS, 2011). Science inquiry
is one of the most popular approaches in science learning activities since it enhances students’ conceptual