First, the guiding ideology:

Yogurt is a common drink in life. Students will have a positive interest in making yogurt through practical activities, and explore the forming conditions of yogurt through experiments. In this way, students can not only experience the production process of yogurt, but also develop a rigorous scientific attitude in activities, improve their ability to solve problems by using comparative experiments, and explore the beneficial side of bacteria (lactic acid bacteria), thus spontaneously collecting more information about intentional bacteria and expanding their horizons.

Second, the activity content and display mode

This scientific practice activity selects the content that is close to students' life and interesting to students, and arranges it before the winter vacation, so that there is enough time to carry out activities during the holiday, and the teacher gives full guidance.

1, experiment: making yogurt

Materials required: 1 cup of fresh yogurt, 2 bags of fresh milk (about 250 ml each), cups or bottles with lids (about 150 ml), 1 metal spoon, 1 bamboo chopsticks, thermometer).

Operating steps: a. Disinfect used containers and tools with boiling water;

B) Boil two bags of fresh milk, cool to about 30 degrees, and evenly pack them into four sterilized cups (or bottles);

C) Add 1 spoon of fresh yogurt into four cups filled with the same amount of fresh milk, stir them evenly, and cover them;

D Put two of them in a warm environment, and the other two in a cool environment, and observe after 24 hours.

2. Record the experimental results, and analyze what kind of environmental conditions are needed to make yogurt.

Complete the experiment according to the correct steps, record the situation of 4 cups of milk after 24 hours, and judge whether the yogurt is ready. If you fail, think about which step needs to be improved, continue the experiment, and compare it repeatedly to find the answer. Finally found the conditions for making yogurt. This stage requires the patience and persistence of scientific research.

3. Collect information about yogurt on the Internet, and also collect and record information about other bacteria that are beneficial to human beings. Organize the recorded data into tabloids, knowledge cards, etc.

Display mode of activity results: 1. Experimental process: written records with electronic photos.

2. Experimental results, conclusion: Small paper

3. Collecting information: a hand-made tabloid with the theme: the relationship between bacteria and human beings.

Three. Implementation of activities

The first stage: organization (before the holiday this semester)

Organize students to participate in scientific practice activities, arrange the content and schedule of this activity, and give students the necessary guidance on activity methods. Emphasize that the success or failure of the activity depends on whether the preparation is sufficient or not and whether there is patience. We must be able to persistently complete this practical activity. At the same time, provide students with the contact number of the organization teacher and give guidance to the problems in the process of activity development.

The second stage (during the winter vacation) exercises

During holidays, students complete practical activities independently. During the activity, students can also communicate with each other or get in touch with the organization teacher to discuss related issues. The practical stage can be roughly divided into the following processes:

1, prepare materials and tools and do yogurt experiment.

2. Record, analyze and study the experimental results, find the conditions needed to make yogurt, and make your own conclusions.

3. Go online or consult relevant books to get more information about yogurt and bacteria beneficial to human beings;

This is the core and most important stage of this practical activity.

Summary of the third phase (next semester) report.

Through half a month's practical activities, every student must gain a lot. At the beginning of the semester, organize them to report their activities, gain experience, exchange and show their experimental process and conclusions. At the same time, in order to expand the influence of the activities, we should choose better students, show their reports to all the students and recommend them to the Association for Science and Technology. From point to point, gradually cultivate students' scientific practice accomplishment.