Too many primary school teachers are unequal to the task of teaching mathematics. They either have inadequate knowledge of this subject or inadequate competence to help children learn, or both.
Primary school is where most criminals begin their antisocial behaviour.
It is no surprise that most prisoners are illiterate and innumerate. In the USA ninety percent of prisoners are confirmed illiterates. Interventions must begin at home and at primary school. Always encourage children to ask questions. Answer their questions truthfully and using concepts, words, illustrations, examples they already know or can grasp.