1. Core content: Understand the time unit "second", initially establish the time concepts of minutes and seconds, and know that 1 minute =60 seconds can solve simple practical problems. (I especially avoid "simply calculating time" here for two reasons: "Curriculum Standard 20 1 1" clearly stipulates that students should "experience the length of time in combination with their own life experiences" in the first learning stage, and calculation and other issues are not involved in the next stage; In Example 2 of the textbook, in addition to solving the problem by calculation, a method of calculating the grid is also provided. In addition, in ExerciseNo. 1 1, and solve the problem in two ways respectively. To sum up, students who have just entered the third grade don't need to change their units and calculate the time when they cross 12. Instead, I advocate using my own life experience to enrich and explore diversified time problem solving strategies. )

2. Core literacy: Feel and understand the meaning of seconds through experiential activities and exploratory activities, and initially develop reasoning ability and estimation ability. The deep learning of primary school mathematics is to cultivate the core literacy of primary school students through the learning of core content. But in this unit, I think the most important thing is to cultivate the estimation ability and reasoning ability of primary school students. The foothold of estimating ability lies in understanding the time unit "second" and initially establishing the time concepts of minutes and seconds. It can be embodied as "time itself is very abstract, and it is difficult for primary school students to master time." Children are in the transition stage from concrete thinking to abstract thinking. Therefore, we must create many materials that are close to the reality of students' life, design colorful experience activities, and strive to transform abstract time into concrete perceivable "quantity" so as to establish an accurate perception of time units. Here, the textbooks use 1 sec, 1 sec,1sec, 30 sec,1min, so that students can establish their own concept of time, from imprecise to more accurate estimation. Of course, this process needs to gradually form the concept of unit time in continuous estimation, verification, adjustment and improvement. )

3. Core thoughts and feelings: cultivate a correct concept of time and develop the habit of observing and cherishing time.

Second, the content analysis

Curriculum Standard 20 1 1 clearly stipulates that "combine your own life experience and experience the length of time". The goal of this course includes not only understanding the concept of time, but also establishing the concept of time. It can be seen that the teaching focus of this unit should be the understanding of time units and seconds and the establishment of the concepts of minutes and seconds. As for choosing the right units and tools to measure the length of time, this learning task can be handled in practice class.

Throughout the entire primary school textbook system, we will find that the "time" arrangement is only four times, as follows:

book number

unit

main content

The first volume of grade one

Know the clock

Have a preliminary understanding of the hour hand and minute hand on the clock face (note that there is no second hand), and can read and write the whole time.

The first volume of grade two

Understanding time

When did you meet? 1 =60.

The first volume of grade three

Hours, minutes and seconds

Know the time unit "seconds", 1 minute =60 seconds, realize the length of time, and simply calculate the time.

The second volume of grade three

Year, month and day

Know the year, month and day, understand their relationship, and understand the 24-hour timing method.

It is not difficult to find that this arrangement is a process from "big" to "small" and then to "big", which follows the development law of students' cognitive time from the middle to the two ends, from near to far. I think it is mainly based on the life experience and abstract thinking ability of primary school students.

As for the unit, on the basis of two time units, students have been studying "second" in detail. This unit * * * consists of 7 pages, including 3 pages of exercises, which are arranged as follows:

The unit unit first arranges the time unit "second" with a small understanding, and understands 1 minute =60 seconds, so that students can grasp the relationship between time, minutes and seconds as a whole; Secondly, experience the length of time, estimate and establish the concept of time; Finally, solve the simple problem about time in many ways.