The steps of scientific methods are usually to observe, make hypotheses, design experiments to test hypotheses, conduct experiments, and determine whether hypotheses are accepted or rejected. Although students can often state the steps of scientific methods, they may find it difficult to implement them in practice. This exercise provides students with the opportunity to experience it scientifically. We chose goldfish as subjects because the students found them interesting and interesting. Of course, you can use any theme or theme. The time required for this exercise depends on you. We recommend three hours of lab time, but the project can be completed in an hour or in a few days, depending on how much you plan to participate. Goldfish tank Optimally, each laboratory needs a bowl of fish. You can work with the whole class, if the class is small, or you can ask the students to divide into groups at will. Show the students a bowl of goldfish. Do some observation on goldfish. Let the students tell the characteristics of goldfish and observe them. They may notice fish’s color, size, swimming position in the container, their interaction with other fish, etc. Students are asked to list what observations involve things that can be measured or limited. Explain how scientists can get data for experiments, and some types of data are easier to record and analyze than others. Help students identify data types that can be recorded as part of the experiment, rather than qualitative data that are difficult to measure or data that they do not have tools to measure at all. Ask students to ask questions they want to know based on their observations. List the data types they may record when investigating each topic. Ask the students to make a hypothesis for each question. Learning how to make a hypothesis requires practice, so students are likely to learn from brainstorming. Write all the suggestions on the blackboard to help students distinguish between hypotheses they can test and hypotheses they can’t test. Ask students if they can improve any assumptions submitted. Choose a hypothesis and design a simple experiment with the whole class to test it. Collect data or create fictional data, explain how to test hypotheses, and draw conclusions based on the results. Let the experimental group choose a hypothesis and design an experiment to test it. If time permits, let students carry out experiments, record and analyze data, and prepare laboratory reports.