At the time of choosing a mattress for children, you have to take into account many factors, especially to ensure the welfare and rest of the smaller, but that does not pose a risk to your health, for example by producing an allergy or problems column.
Actually what mattress to buy for children depend on the age of the child as well as the environment they live. Just keep in mind that it needs change depending on the age of the child, so the recommendations are based on the age group:
For babies a firm mattress is recommended, as this reduces the incidence of sudden infant death. Thus a good choice would be the foam mattresses with memory, to adapt perfectly to the body surface where there are no pressure points on the head is higher, but it is distributed in a uniform manner.
For older children, from about 3 years, a mattress that allows freedom of movement and possessing antiallergic properties and made with a fabric that prevents thermal temperature changes is recommended. It will also be important to note that the greater weight of the child shall be a firmer mattress, to ensure proper rest and wellbeing.