Phosphorus is a chemical element with symbol P and atomic number 15. As an element, phosphorus exists in two major formsâ white phosphorus and red phosphorus âbut due to its high reactivity, phosphorus is never found as a free element on Earth. Instead phosphorus-containing minerals are almost always present in their maximally oxidised state, as inorganic phosphate rocks.
Ages & Stages â Preschool Children. Three and four-year-old children are often called preschoolers. Preschool children want to touch, taste, smell, hear, and test things for themselves. They are eager to learn. They learn by experiencing and by doing. Preschoolers learn from their play.
Instead, a child of this age is considered a preschooler, even though children younger than three often attend preschool (and many children never attend preschool at all. This perspective on toddlerhood is echoed by the Center for Disease Control (CDC). According to their website toddler are one to two years of age.. The beloved What to Expect During the Toddler Years, also state that toddlerhood includes the second and third years of a child's life.