One of the main indicators of the formation of the system is “Numbers and calculations: The order of numbers on the number line”. It allows you to determine the level of formation of a visual – figurative understanding of a set of natural numbers and the ability to use a number line to determine the place of a number in a sequence from 1 to 20, as well as in solving equations and inequalities.
For children, age 5, the numerical axis is a clear geometric image of the set of natural numbers. It consists of an origin point and a ray that corresponds to positive numbers. The natural order of the points on the line in such correspondence is consistent with the ordering of the numbers. The numerical axis for children aged 5 is used as a visual aid for determining a sequence of numbers from 1 to 20, establishing order in counting, solving simple equations and inequalities. Line segments represent numerical intervals.
The test results showed the presence of a well-formed idea of a natural number as a result of counting and measurement. However, the student makes mistakes when determining the place of a number in a sequence of numbers from 1 to 20 and makes inaccuracies in determining a number within 20 when solving equations and inequalities.
According to the test results, it can be concluded that the student uses a numerical segment to compare and choose the correct answer. Which, in turn, allows us to talk about the process of development of visual – figurative thinking.
To develop this skill, we recommend regular exercises with materials:

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