“My ten-year-old son, 4th grade student, for a few days he can not break into playing with newly met peers. Translating or pushing him almost by force into a group of other children is of no use. Only after a few days does he make contact, and only then, when peers ask him, for example, whether he will play football with them. Then the game starts for good and I am over it”, and it's even hard to summon him from the yard. How to cure him of this shyness?”
Please, sir, at this age, a child is unlikely to be cured of shyness. There are many indications, however, that your son is either an only child, or the youngest child in the family, where there is a large age difference between siblings. As a result, certain social skills are lacking, which are needed in a group of children. Personally, I don't see any need for treatment or any specialist help for the boy. I would just give him time. If you create a situation for him, thanks to which the son will often be among his peers (but not in the yard, or rather, in organized groups, such as the sports section, pattern shop, etc.), where he will be able to interact with them – his reactions will change quickly.