Improving skills in mental calculation. One of the main objectives of teaching mathematics in primary schools – to offer students computer skills, and skills of a strong, conscious, and the skills of addition and subtraction Within 20 should be brought to automaticity. Assimilation of mathematical knowledge depends on both the quality and quantity of the exercises used. Each teacher strives to allow students as much as possible performed various tasks and exercises in class, and trying to fulfill their writing, believing that the more satisfied the written tasks, the better. However, the schools showed that high school students who do not know the verbal accounts, as a rule, can not cope with written work, often lying down in time.

To achieve accuracy and fluency of oral calculations for all three or four years learning every lesson Mathematics should be allocated 5 minutes to conduct training exercises in mental calculation required under the program each month. This requirement is implemented at the stage of the lesson, traditionally known as oral account. The main objectives of this phase are: 1. and correction of certain knowledge and skills necessary for conscious perception of the material and self-employment. 2.Kontrol teacher for state of knowledge of students. 3. prepare students to accept the new material is rational to choose the content – it means the following requirements: 1.Obem alleged assignments should be necessary sufficient for further work in the classroom. 2.In the system proposed for the oral accounts of jobs should be clearly defined place each of them.