Developmental Milestones Ages INCLUDE = Ages BIRTH-FIVE YEARS (Kindergarten). PREVIEW shows ONLY age 3-4 years. SKILLS ADDRESSED INCLUDE: cognition, pre-reading, language, social, visual-perceptual skills, self-care, gross motor, among others. Parents, teachers and service providers are best prepared when they are informed of appropriate developmental milestones in order to know what skills should be obtained within a certain age range. It helps to assess which skills are weak and in need to attention. This developmental milestone tool helps identify red flags as well as the skills that are appropriate for children ages birth through age five (Kindergarten).