Hello judges!(bow) I am applying for the primary school mathematics teacher No. 03 candidate, today I try to talk about the topic is "knowing decimals", now I will start my trial lecture.
Hello students, please be seated. Before the class, the teacher will give you an interesting paragraph, please be serious, and the teacher will ask you questions after reading. The students are finished, and the children in the ** and the mothers buy erasers and children's scissors together, but this child can't read the **label, which classmate can help him?(pauses to look around) OK!This male classmate, you can help him. The male classmate said that he also did not understand the label. But it doesn't matter, this classmate was able to stand up and show that his courage is commendable!Everyone gave him a round of applause!(Applause) Does anyone know, please raise your hand!Good!Tell me about this female classmate. The female classmate said that the ** of an eraser is 08 yuan;The ** of a pair of scissors is 39 yuan, which is expressed in decimal places on the label. This classmate answered very well and his voice was very loud!So let's learn Xi "Understanding Decimals" today. (Board book: Knowing decimals).
Students, please look at the 4 ** on the big screen, the first ** is an aunt buying tomatoes, and the weighing table shows ** is 345。The second ** is the ** of the pencil and the ballpoint pen on the shelf, which are 0$85 and 260 yuan. The third ** is the doctor taking the child's temperature, and the temperature is 366. Normal body temperature. The fourth is for children to purchase a child ticket, which stipulates the height standard for children, which are 12 meters and 15 meters. Please observe carefully how these numbers differ from the integers we have learned Xi beforeThe discussion was divided into four groups, after which each group was invited to send a representative to report.
The discussion is over, and I just saw that everyone had a very heated discussion. Now we're going to ask for four groups of generations.
The representatives of all four of our groups reported the results and all agreed that the numbers had dots, while integers did not have dots, and that the numbers were read differently than integers. Yes, these decimals are indeed different from integers in that they have a little dot, and numbers like this are called decimals. (Board book.)5 is called a decimal).
Students, do you remember the scores we used to learn?There is a line in the middle of the fraction, what is this line called?What is the name of a dot in the middle of a decimal that we see today?After everyone had thought about it, I asked the male students in the blue shirts in the last row to answer. He said that the line in the middle of the fraction is called the fractional line, and the dot in the middle of the decimal is called the decimal point. Correct answer!This student's ability to relate his previous knowledge to what he has learned today shows that he is good at thinking and is also a good example for other students to learn Xi. That's right!The dot in the middle of the decimal is called the decimal point. (Board book: The dot in the middle of the decimal is called the decimal point).
We've just learned about decimals, so how do we pronounce them?If anyone wants to be bold enough to try and read the first number, please raise your hand!The tall female classmate in the middle hand, you read the first number out loud. This classmate put 345 reads: three-four-five. (Board book: 3.)45 reads: three four five) Very good, please take a seat!There are a few numbers at the back, and I hope that students can read them boldly like this student. After everyone spoke actively, the teacher found that everyone basically mastered the reading of decimals, so is there any rule for the reading of decimals?Please discuss with each other at the table and draw conclusions together. After mutual discussion at the same table, you who are smart have found that there are certain rules for the reading of these decimals, and everyone follows the teacher to say the rules of decimal reading: the integer part is read according to the whole number, the decimal part is only read according to the number itself, and the decimal point is read as "point".
Students, now please look at the big screen, the teacher has brought you a warm home, there are beautiful furniture in the home, and the furniture you see is marked with dimensions. Let's start by looking at the table size, which is 14 meters, how to represent it if it is expressed as a fraction?What is the relationship between meters and decimeters?Please discuss it in the four groups you have just divided, and the teacher will also ask the group representative to give a report. The discussion ended, and each group came up with a result of 14 meters is expressed as a fraction and is 1 and 4 tenths of a meter. The teacher tells you that in addition to being a fraction, 1 decimeter can also be expressed as a decimal as 01 meter, that is, 1 meter is divided into 10 equal parts, each part is 1 decimeter, which is a meter, and can also be written as 01 meter. After the exchange and Xi just now, it seems that the students have mastered the relationship between fractions and decimals. We have encountered many practical problems like this in our lives, and now please take a look at the example on the big screen: Wang Dong is 1.3 meters tall, how to express it if he uses meters as a unit?Using the method we have just learned, we can divide 1 meter into 10 equal parts, each part is 1 decimeter, 3 decimeters is 3 10 meters, and with a decimal is 03 meters, 1 meter, 3 decimeters, expressed as a decimal number, is 13 meters. (Board book: 1 decimeter = 0.)1 meter.
Students, through the learning Xi of this lesson, we have a preliminary understanding of decimals, understand that we can see decimals everywhere in our lives, and now the teacher has prepared some interesting Xi exercises for everyone, please take turns to practice Xi in each group, to see which group takes the shortest time and has the highest accuracy rate. The fun Xi is over, and it seems that the students in each group are very active and can answer the questions raised by the teacher correctly, which is very good!
Now please think about what is the main content of today's Xi, and what have you gained?Summarize it yourself, write it in your own Xi practice book, and talk about it with your tablemates. Good!The teacher just saw that the students were all seriously summarizing what they had learned in this lesson and sharing their gains with their peers!