This study aims to identify students' misconceptions regarding covalent bonds. Seventyseven graduate students in the middle of Indonesia participated in the study. Data were collected in three stages. First, misconceptions were identified by using the Semi Open Diagnostic Test. Ten students who experienced the worst misconceptions were interviewed. Lastly, textbooks were reviewed. Content analysis was used to analyze the misconception data. We identified eight primary misconceptions, namely: (i) a covalent bond is formed between two atoms with a pair of free electrons; (ii) each atom in a stable molecule must follow the octet rules; (iii) a covalent bond is polar if the electron affinity of two bonded atoms is different; (iv) the form of the molecule depends on the number of atoms bonded to the central atom; (v) nonpolar molecules have a dipole moment m > 0; (vi) all bonds in polar molecules are polar, while all bonds in non-polar molecules are non-polar; (vii) the number of bonds depends on the electronegativity of the atoms; and (viii) bond length depends on the type of bond. The main causes of student misconceptions are as follows: (i) incomplete information; (ii) difficulty understanding basic concepts regarding covalent bonds; and (iii) lack of effective communication between students and teachers. The results suggested the following implications for teaching: the teacher should identify misconceptions about prior knowledge or concepts prior to teaching the basics, identify reference book learning, and facilitate effective communication so that information received by the student is complete and correct. # 2016 Wiley Periodicals, Inc. J Res Sci Teach 54:520-537, 2017

Abstract—This study aims to analyze students' scientific critical thinking skills through learning with edmodo-based blended learning models. This study is Pre-Experimental using one group pre-test post-test design involving 35 class VIII students at Public Junior High School 10 Jember, Indonesia. The instru-ments used were teacher activity observation sheets, student activity observation sheets, scientific critical thinking skills assessment sheets, and student motivation sheets. Before and after learning activity, students are given the same initial test (pre-test) and final test (post-test). The collected data was analyzed by quantitative descriptive analysis. The results of the study show that: (1) students are motivated in classical learning by 78.13% with motivated criteria. The highest value is on the likes and active indicators using Edmodo, which is equal to 88.47% and the lowest value on the indicator of activity asks questions and opinions at edmodo, which is equal to 70.93%; and (2) there is an increase in scientific critical thinking skills of students with a mean n-gain of .32, with the criteria being moderate. The highest value is achieved on the indicator of fact analysis, which is equal to .55 and the lowest value on the indicators of delivery of argumentation, which is equal to .19. The conclusion of this study is that science learning with an edmodo-based blended learning model can motivate learning and improve scientific critical thinking skills of junior high school students.

No abstract

<p class="0abstract">This study aims to develop edmodo-based interactive teaching materials as an alternative media for science learning to improve critical thinking skills of junior high school students. This type of research is Research and Development (R&amp;D) with ADDIE (Analyze, Design, Development, Implementation, and Evaluation) models. The research subjects were 28 students of grade VII in Jember district (Indonesia) who were obtained by cluster random sampling technique. Data were collected using validation sheets, observation sheets, critical thinking skills tests, and students responses questionnaires. Data were analyzed using descriptive analysis, normalized gain (n-gain), and paired sample t-test. The results show that edmodo-based interactive teaching materials can be used as an alternative media for learning science in junior high schools because they meet the following criteria: (1) validity, in terms of the validity assessment score of 3.60 (from the range of scores from 0 to 4) in the criteria are very valid, (2) practicality, in terms of the score of learning feasibility of 3.20 in good criteria, (3) effectiveness, in terms of an increase students critical thinking skills were statistically significant at α = 5% with an average n-gain of .71 in high criteria, and student responses of 83% in very good criteria.</p>

No abstract