Articles A Novel Tool to Facilitate the Learning of Thermodynamic Principles by Undergraduate Students of the Biological Area* h S Received for publication, March 31, 2009, and in revised form, June 11, 2009 Eduardo O. Carvalho‡, Marcelo K. Araki‡, Se ´rgio F. Freitas‡, Carlos M. G. de Godoy‡, Adelaide Faljoni-Alario§, Pedro L. Frare-Junior‡, and Iseli L. Nantes‡¶ From the ‡Centro Interdisciplinar de Investigac ¸a ˜o Bioquı´mica–CIIB, Universidade de Mogi das Cruzes–UMC, §Centro de Cie ˆ ncias Naturais e Humanas–CCNH, Universidade Federal do ABC–UFABC This study describes the application and evaluation of a novel didactic tool (thermodynamic device) developed for students in the area of biology who have conceptual deficiencies that render the learning of thermodynamic principles difficult. Systems of communicant vessels with equal and different com- partments were constructed to correlate the equilibrium constant of the reactions and reagent/product ratios with the concept of standard and nonstandard Gibbs free energy changes (DG8 and DG, respec- tively). The communicating vessels were filled respectively with equal and different volumes of a dye aqueous solution followed by the opening of a faucet that coupled the vessels. This procedure allows liquid flux leading to the movement of internal propellers. The movement of the propellers turns on an electronic circuit that processes the information to exhibit the energy released by the movement of the solution toward equilibrium. The thermodynamic device was evaluated regarding the efficiency of con- tent comprehension and retention of the gain by challenging students to answer five subjective ques- tions 1 week after a regular teaching module about thermodynamics. The overall mean score obtained by the students who accessed the thermodynamic device (7.0) was significantly higher (p < 0.01) than the mean score of the control group (3.4). The thermodynamic device increased twofold the percentage of students who gave more than 50% correct answers. The efficiency of the didactic tool was also eval- uated and corroborated by objective questions. In conclusion, the use of the thermodynamic device was highly effective in improving the understanding of thermodynamic principles by undergraduate biology students. Keywords: Original models for teaching and learning, teaching and learning techniques methods and approaches, sources of difficulties and teaching strategies to correct difficulties, student conceptual and reasoning difficulties. Efforts initiated since the 1980s by successive Brazilian governments [1] were efficient in increasing the number of 7- to 14-year-old Brazilians attending school—from 79.4% in 1991 to 94.5% in 2000—but had little impact on increasing the proficiency of the pupils [2]. To over- come this problem, Brazilian governments have adopted a systematic policy of teaching evaluation encompassing the fundamental to the graduated levels and including SAEB (in Portuguese, Sistema de Avaliac ¸a ˜ o do Ensino Ba ´ sico,—Evaluation System of Basic Education), ENEM (in Portuguese, Exame Nacional do Ensino Me ´ dio— Evaluation System of Intermediate Education), ENADE (in Portuguese, Exame Nacional da Avaliac ¸a ˜o do Desempenho do Estudante, Evaluation System of Undergraduate Education) and the efficient evaluation system developed by CAPES (in Portuguese, Coordena- doria de Aperfeic ¸ oamento de Pessoal do Ensino Supe- rior , Evaluation System of Graduate Education), which has contributed significantly to the high quality of the Brazilian graduate school system. The results of successive evaluation have revealed that, in the actual scenario of intermediate and under- graduate courses, teachers are challenged to teach specific discipline contents to students who are not only deprived of fundamental concepts but also lack the skill to handle abstract concepts. In the case of courses in the biological area, there is also the hard task of providing enough technical background in bio- chemistry to permit students to follow the vertiginous scientific and technological advances characteristic of the current day. Particularly for chemistry and correlated h S Additional Supporting Information may be found in the online version of this article. *This work was supported by the Brazilian research founding agencies Fundac ¸a ˜ o de Amparo a ` Pesquisa do Estado de Sa ˜o Paulo (FAPESP), Fundac ¸a ˜ o de Amparo ao Ensino e Pesquisa da Universidade de Mogi das Cruzes (FAEP-UMC), and Conselho Nacional de Desenvolvimento Cientı´fico e Tecnolo ´ gico (CNPq). ¶ To whom correspondence should be addressed. Centro Interdisciplinar de Investigac ¸a ˜o Bioquı´mica–CIIB, Universidade de Mogi das Cruzes–UMC. Av. Dr Ca ˆ ndido Xavier Almeida Souza, 200, Mogi das Cruzes–SR, Brazil 08780-911. Tel.: þ55114798-7103; Fax: þ55114798-7102. E-mail: ilnantes@umc.br. This paper is available on line at http://www.bambed.org DOI 10.1002/bmb.20311 271 Q 2009 by The International Union of Biochemistry and Molecular Biology BIOCHEMISTRY AND MOLECULAR BIOLOGY EDUCATION Vol. 37, No. 5, pp. 271–278, 2009