Mathematics was designed to aid human understanding. The more mathematics is related to the subject, the better our quantitative understanding of the subject. Calculus is a great tool in this regard. If we look at the individual tools of mathematics, they may be useless. But when different sections of mathematics are used together, they are sure to help in all subjects. One more thing: "If we don't use a tool, it doesn't mean it's useless. You can do a lot of things with it, but we don't need it in everyday life, so we just don't use it." Specifically, we look at the examples: - 1) The Minister: one of his main tasks is campaigning. He should run more campaigns in areas where he has a chance of winning than in areas where he is sure to win. This is evidenced by the review of the past elections, when the general opinion prevailed among the people. He should also campaign in areas where there is a high probability that people will come to his lecture and vote. When he becomes a minister, he must seek the development of the region. This applies to all branches of mathematics. Its long-term goals, promises, etc. The main thing is to manage the available funds. Suppose he decides to build a bridge, overpass or any similar infrastructure project, he needs to think about the funds for construction. If he keeps some kind of travel tax, how much should he keep? This can be decided by how many people will use it every day? How much is he going to collect? Inflation, etc. All this is determined by calculus. 2) Kindergarten teacher: she should monitor the child's growth. Some kids can pick up on things quickly. You don't have to spend a lot of time on them. Teachers should focus more on the average child. I am also sure that not everyone will understand everything. Thus, the teacher has to make some calculations to determine when the right time will come to move on to the next topic. If it builds a graph "how many people understood depending on the time". It will definitely get a Gaussian curve. This will be useful for later classes. She can ask all the students a simple question and conduct this survey. Also, marks scored by students will have a Gaussian curve shape. Now suppose she has to convert it some other grading standards. (Example from a scale of 100 to relative grading of scale of 10).It would be good for her to know of calculus. She can figure out How much area (integration) is covered by the above mentioned graph? How much percentage of people are present in which area? What is the average grade she wants to keep etc. etc. These are some of things which directly come to my mind. Tell students to think more in this line and they will surely find out more uses. Or better still put some enthusiastic calculus teacher in the above post for a day and He/she will think of a 100 more uses. Some might argue that these are special cases, but remind them that the job requires not only the ability to do everyday work, but also special cases that may arise.