First, the topic (topic) should pay attention to "practicality", "feasibility" and "creativity". "Practicality" means that the topic should have certain practical value in production, life or science, that is, the research results may be transplanted and applied to serve mankind and have certain value in science. "Feasibility" is to proceed from reality, that is, to determine the subject from our knowledge base and manpower, existing experimental conditions and funding conditions, which is a goal that can be achieved through hard work. Students should write short essays on topics that are "small", not "big", but "complete". "Creativity" means that the topic should be novel and innovative, the research methods should be innovative, and others should not simply repeat the experiments. Second, after the research method topic is determined, it is necessary to choose a suitable research method to complete the topic. There are three main research methods: investigation, observation and experiment. Investigation method is to investigate the regularity of composition, quantity and distribution of some organisms in a certain area, such as investigating insect species, species and quantity changes of some birds and animals, medicinal plants, anti-pollution plants and indicator plants in environmental protection, etc ... These investigation results may be adopted by relevant departments and play a certain social and economic benefits. This research method costs less, does not need complicated instruments and equipment, and can be carried out in general schools. Observation is a careful observation of some individuals of a certain organism to understand their living habits and the laws of growth and development. In the process of research, there should be a certain number of observation objects, because if only one individual is observed, it will be accidental and the conclusion may not be universal and representative. Also pay attention to repeated observation, you can set more observation points at the same time, and draw scientific conclusions. At the same time of observation, it will be better if we can pay attention to collecting and making life history specimens. Investigation and observation are generally carried out without changing the environmental conditions of living things, while the experimental rule is to artificially change a certain factor in the environment (such as food, temperature, light, etc.). ), observe the impact on organisms and find out its regularity. The experimental method should be scientific. For example, the topic "Effects of Different Feeds on the Development of Toad Tadpoles" can be divided into three groups: animal feed, plant feed and mixed feed. During the feeding process, only three groups are allowed to feed different tadpoles in the experiment, and other conditions, such as the source and size of tadpoles, containers, water quality, water temperature and illumination, are required to be as same as possible to avoid other factors affecting the scientific nature of the experimental results. There should be a certain number of tadpoles, about 20 in each group. The number is too small, and the experimental results are prone to contingency, which does not explain the problem; Too much will bring problems to reproduction and observation. Third, writing a "short paper" is a summary of students' own research results, so writing can be described by the first person "I" or "we". "Small papers" generally include: ① topics. The title of the paper should be concise, novel and attractive to readers. ② Introduction. At the beginning of the article, you can write a simple introduction, explaining the purpose of this research, how the author came up with the idea to carry out this research, and so on. ③ Materials and methods. It is necessary to clearly write down the objects of investigation and observation, experimental materials, sources of materials, research methods and instruments and equipment used. Four results. The result is the argument part of the paper, if possible, it is best to express it in the form of data and organize it into a table; If you can draw another picture, it will be more vivid and convincing. ⑤ Discussion. Discussion is the argumentation and argumentation part of the paper. After analyzing the obtained data, we draw a scientific conclusion, that is, an argument, and explain it theoretically. ⑥ Conclusion and references. You can talk about the practical value of this research; Some can also talk about the shortcomings of this study and indicate the references.

Model essay 1: Why is the trunk round?

In the process of observing nature, I happened to find that the shape of the trunk is almost round-an empty cone. Why is the trunk conical? What are the benefits of a conical trunk? In order to discuss these problems, I made more in-depth observation and analysis.

With the help of my tutor, I consulted relevant materials and learned that the stems of plants have the functions of supporting plants and transporting water and other nutrients. The stems of trees are mainly composed of vascular bundles. The supporting function of stem is mainly borne by wood fibers in xylem. Although the stems of woody plants will become thicker year by year, in a certain time range, the number of woody fibers in the stems is certain, that is, the cross-sectional area of the stems is certain. Then, based on the assumption that the cross section of the trunk grows into different shapes, we design experiments to explore the reasons and advantages of conical trunk.

Through experiments, we find that when the cross-sectional area and length of (1) are fixed, the vertical supporting force of triangular columnar objects is the largest and the lateral bearing capacity is the smallest; The vertical supporting force of cylindrical objects is not as good as that of triangular cylindrical objects, but the lateral bearing force is the largest; (2) For trunks with the same mass and different shapes, the short conical trunk bears the largest wind force; (3) Wind is a natural phenomenon, which affects the cross-sectional shape and height of trees. The approximate cone-shaped trunk has a low center of gravity, and the huge root system is connected with the earth, so the center of gravity drops lower and the stability is greater; (4) The cross section of the trunk is round, which can reduce the damage, has stronger mechanical strength and can resist the wind attack. At the same time, under the action of the wind, the bending degree of the trunk is similar everywhere. No matter which direction the wind blows, the resistance of the trunk is similar, and the trunk is not easy to be damaged.

The above experiments reflect the laws of nature, and nature enlightens us: (1) A columnar object with a triangular cross section has the greatest vertical supporting force, and its shape can be used in buildings, such as angle steel; (2) A circular object with a circular cross section has the largest lateral bearing capacity, and similar building materials can be found everywhere, such as TV towers and telephone poles.

In the process of observation, experiment and analysis, I gradually explained and revealed the mystery of conical trunk, increased my knowledge, and combined my knowledge with practice, which not only consolidated my knowledge, but also improved my interest in learning, and initially learned the scientific observation and analysis methods.

Fan Wener: What effect does vinegar have on flowers?

Vinegar is a common condiment in life, while flowers can purify the ecological environment and beautify our life.

Have you ever thought about the relationship between vinegar and flowers? We explored the subject with curiosity. According to people who have rich experience in planting flowers, applying some vinegar on potted flowers can improve the growth of potted flowers and increase flowers, which are bright and leafy. We soon confirmed this in the experiment.

Do different concentrations of vinegar have different effects on flowers? This is the second stage of our experiment. We select four pots of gypsophila paniculata, primrose and Chinese rose with the same growth and divide them into four groups. Each group (three pots) has three kinds of flowers, which are numbered and labeled respectively. At the same time, we prepared edible white vinegar into three solutions with different concentrations: 1% (pH 2~3), 0.0 1% (pH ≈4) and 0.000 1% (pH ≈6), and sprayed vinegar on three groups of potted flowers once a day, while the fourth group did not. Observe and record the growth of flowers every five days.

The results of this experiment are as follows: spraying low concentration vinegar (pH ≈6) has no obvious effect on these flowers; The flowers sprayed with moderate concentration of vinegar (pH ≈4) are obviously better than other groups, with more buds, earlier flowering, richer colors and longer flowering period. Spraying high concentration vinegar with pH value of 2-3 will make the flowers wither prematurely.

Through this experiment, we can tell you that spraying vinegar properly when planting flowers can make flowers grow better. But to master the concentration of vinegar, excessive acetic acid will harm flowers.