Learning and development stage
The multiplication formula may still be in the learning and development stage for children in kindergarten class, and may not be fully mastered.
basic concept
Children need to master addition and basic counting ability before learning multiplication formula. If children have not fully mastered these basic concepts, learning multiplication formulas may be confusing.
individual difference
Mental retardation is not an accurate medical term and cannot be used to describe children's abilities at will. Every child has his own unique development track and potential. We should respect their individual differences and provide them with appropriate education and support.
Consider in many ways.
Don't think that children are mentally retarded just because they can't multiply formulas. Instead, we should consider and analyze the child's situation from many aspects and give necessary support and help.