Through in-depth exploration of the scientific knowledge permeated in the context of “tofu making”, this article introduces how to fully extract soybean protein, how to convert raw soybean milk into tofu, and mainly presents the knowledge of protein properties, colloidal stability and coagulant promoting soy protein coagulation principle during the production of tofu. Then the structural characteristics of tofu products were extended appropriately, and the development and cutting-edge applications of hydrogels were introduced. To deepen students’ understanding of what they have learned, to broaden their horizons, to cultivate students’ attitude towards life and to cultivate the fun of scientific research.

This paper analyzed the content requirements and teaching tips of the “Organic Chemistry Fundamentals” module in the 2017 version of the senior high school chemistry curriculum standards, and clarified the core ideas of the subject and the expressive requirements that point to core literacy. This paper expounded the compiling ideas of the new high school chemistry textbook Basics of Organic Chemistry of Luke edition, described the advanced development path of students’ organic subject literacy, and put forward suggestions for the use of the new textbook accordingly.

In March 2020, the Strategic Visioning Expert Group organized by the OECD released PISA 2024 Strategic Vision and Direction for Science, which plans to introduce a new assessment dimension “Scientific Identity” into the PISA Science Framework. Based on this framework, this paper probes into the connotation of science identity, the phased process of scientific identity development and the important dimensions of scientific identity evaluation, and discusses the significance of scientific identity evaluation to the practice and evaluation of science education.

From the perspective of evolution relationship, the chemical process test questions is a type of senior high school entrance examination chemistry questions derived from the chemical block diagram inference test questions. Because of the different contents and requirements of the curriculum standards and the different ideas of the proposition, they play different roles in the evaluation and guidance of the junior high school graduation questions. With the reform of junior high school graduation questions, it is a trend that the chemical process test questions gradually replace the chemical block diagram inference test questions, which will have a positive and far-reaching impact on junior high school chemistry teaching.

On the basis of the approaches to core ideas construction, there were five cognitive frameworks introduced in this paper: the students’ understanding of the progressive model of matter concepts, the use of Rasch model to construct the progressive model of students’ learning of matter concepts, to develop the learning progression model of matter structure by the landscape approach, the conceptual profile zones for substance and the conceptual profile of substance. In addition, water understanding was taken as an example to analyze its construct map and outcome space. Moreover, based on the analyses of scientific curricula standards from nine countries or regions in the United States, the United Kingdom, Australia, Ireland, Singapore, Alberta, Ontario, Taiwan and Chinese mainland, the core ideas of matter in stages from grade one to nine were generalized by the researchers. Additionally, the progressive dimensions of matter were divided from three perspectives of component analysis and identification, properties and applications as well as changes and transformation. Moreover, the paper introduced the advanced measurement method of the core ideas of “matter” and its enlightenment to science education in China.

Through the comparison and analysis of the content of electrochemistry in the old and new PEP textbooks, the new version focuses more on the social hot spots and scientific frontier chemistry problems in the theme, pays more attention to the connection of knowledge in the overall content arrangement, pays more attention to the refining and generalization of understanding ideas and methods in the textbook column setting, and highlights the educational function of chemical experiment in the experimental content arrangement. The new version of the textbook puts forward higher requirements for practical teaching. In the actual teaching, teachers need to pay attention to the extraction and explicit of cognitive ideas and methods, optimize the selection of situational materials, and give full play to the core literacy training function of chemical experiment.

This paper takes the concept of salt bridge as the project, starting from the concept of “bridge”, three project tasks are set up based on the function of bridge, the basis of bridge selection and the composition and function of bridge in actual battery; four project tasks are set up based on the concept of “salt”, and the influence of salt type and concentration on the current of primary battery. The concept of salt bridge is associated with the battery in real life by project tasks, so that students can learn the ability to solve general problems through experimental methods, the ability to integrate theoretical knowledge with practical engineering technology, and the ability to integrate interdisciplinary knowledge and model construction.

By analyzing the content structure of the introduction of the three latest revised compulsory teaching materials for senior high school chemistry, it concluded that teachers should transform teaching from the introduction to the preface, and sublimate the understanding of the textbooks. It is necessary for teachers to reconstruct the preface of the textbook from four dimensions, including the description of the textbooks’ compilation intention, the subject characteristics and development introduction, the main content and characteristic analysis of the textbook, and the interpretation of the subject’s educational value and the learning suggestions, as well as enlighten students’ understanding and structured thinking of the subject and textbook, and to be the advance organizer of the overall understanding of the subject.

Through the comparison and analysis of the new and old curriculum standards and teaching materials, the cognitive mode, big concept and teaching objectives of the aqueous solution theme are determined. The appropriate situational materials are selected around the teaching objectives, and the unit teaching is guided by the big concept. In the process of solving the real problems, the basic perspective and thinking of students’ understanding of aqueous solution are developed, and the development of students’ core literacy of chemistry is promoted.

“Leading to paradox” is a kind of teaching method with wisdom in creating teaching situation and guiding students whose core idea originates from the paradox thought of the allosteric learning model. It aims to create a reflective learning process of “affirmation, negation and affirmation” for learners. There are four ways to create different paradox situation of “concept and concept” “theory and experiment” “theory and theory” and “experiment and experiment” in the chemistry teaching design in senior high school, so as to promote the transformation from old concepts to new concepts and develop the higher-order thinking ability. In the implementation of “leading to paradox”, we should pay attention to the selection of appropriate knowledge content, the adjustment of students’ psychology and the provision of abundant supporting materials.

Studying how do high school students to solve problem of element inference can deepen the understanding of chemical problem solving. Using cluster random sampling, students from each class of senior 2 and senior 3 in a senior high school in Hainan province were tested, using the adapted problems of college entrance examination as a tool, using NVivo to analyze students’ written reports, it was found that there were many types of solution and order of elements. This diversity was caused by different ways of representing and solving strategies. Inspiration to curriculum and teaching: using scientific representation, and promote the construction of students’ scientific representation; emphasis on algorithm strategy, correct deviations caused by heuristics.

The research employs video analysis technique to evaluate the innovative ability of outstanding pre-service teachers in chemistry classroom. The participants were chemistry group players in Toshiba Cup Teaching Skills Innovation Competition. NVivo software was used for data analysis from four dimensions, involving teaching idea, teaching context, experimental design and teaching technique. The results showed that their teaching ideas were novel, but insufficient in practice. Contexts were vivid, but not closely associated with topics and students. Experimental designs were unique, but there was much room for improvement on the level. Teaching techniques were advanced, but still needed deep integration. The research provides implications for the cultivation of innovative outstanding chemistry teachers.

American The NSTA/ASTE 2020 Science Standards for Teacher Preparation was revised for the implementation of the New Generation of Science Education Standards, based on the latest research results of science education, with particular emphasis on the importance of subject content knowledge, and supplementing the requirements for the essence of science and scientific culture, It also strengthens the understanding of engineering and technology, cross-concepts, and subject concepts, highlighting the application of the law of learning advancement in the training of science teachers. In addition, corresponding changes have been made in the dimensions of subject teaching methods, learning environment, safety, and the impact on student learning. Therefore, it enlightens us that the standard for science teacher preparation which needs to refer the international reform trend and have Chinese characteristics should be issued. Content knowledge is important for science teachers’ professional development. Science teacher training should be based on the regular of learning progressions and pre-service teacher training should pay more attention to build learning environments.

Stoichiometric ratio has important applications in middle school teaching and actual production. Aiming at the shortcomings of the concept teaching of stoichiometric ratio, this research uses the handheld technology TQVC conceptual cognitive model as the theoretical basis to design experiments to determine the stoichiometric ratio of neutralization reaction. Based on the equimolar continuous change method, this experiment uses a temperature sensor to measure the temperature change data of reactants with different molar ratios to find out the reactant molar ratio corresponding to the maximum temperature change difference, that is, the stoichiometric ratio, to help students from a quantitative perspective understand the concept of stoichiometric ratio.

Starting from the color of sodium combustion products, combined with the theories and experiments, this paper discussed three issues about the existence of a small amount of black material in the products, changes in the color of the product after combustion and the composition of the final products. The conclusion was that the products of sodium combustion were mainly white sodium peroxide and yellow sodium superoxide.

Whether carbon dioxide can react with calcium chloride solution and produce white precipitate is a mistake prone point for students. In order to eliminate students’ misunderstandings on this issue,this article conducts a comprehensive analysis from the perspective of the formation of precipitation,whether the reaction can proceed spontaneously,and the contradiction of reactions between substances. So that students have a clear understanding of whether carbon dioxide and calcium chloride solution can react in essence.

Taking the published literature on model and modeling research published on China National Knowledge Infrastructure (CNKI) from 2000 to 2020 as the research object, statistical analysis was carried out on the three aspects of literature quantity, literature content and literature distribution. It was found that the number of research on model and modeling in domestic chemical education in the past 20 years has increased significantly since 2017. The literature content involves teaching research, ability assessment, connotation interpretation, text analysis and literature review. The literature mainly comes from normal universities and chemical education periodicals, and the author group is relatively scattered. Based on the analysis of the current situation, this paper points out the shortcomings of the current research in order to provide some references for the follow-up research in this field.

Based on the analysis of 60 literatures on the application of SOLO classification theory in high school chemistry education from 2015 to 2020, this paper summarizes five aspects of the application of SOLO classification theory in junior high school and senior high school chemistry education: (1) guiding the preparation of exercises and the establishment of scoring standards, (2) analysis of senior high school and college entrance examination questions, (3) guiding teaching practice, (4) guiding empirical research on learning psychology, (5) guiding teaching evaluation. And from these five aspects, the application of chemistry research in junior high school and senior high school is compared, and the successful experience of senior high school teachers is summarized to provide reference for the relevant research of junior high school teachers, and suggestions are put forward for middle school teachers to use SOLO classification theory to solve problems in teaching.