Ages & Stages

While all children develop differently, it helps to know if they are meeting typical milestones and how you can support their healthy development and learning.


Your Child @

Below are materials to help you understand what’s happening at different stages of your child’s life and how you can help nurture their growth and development. All have been reviewed and approved by the American Academy of Pediatrics.


Arizona’s Infant and Toddler Developmental Guidelines

First Things First and other key partners in Arizona’s early childhood system developed this detailed resource to help parents, families and other caregivers understand the appropriate development of children from birth to age 3, and also what they can do to support children’s healthy development and learning.

Recognizing that all children progress differently, these guidelines describe expectations about what infants and toddlers should know (understand) and do (competencies and skills) across the full range of development:

  • Social and emotional development, which includes trust, self-regulation, and relationships with other children
  • Approaches to learning, which includes persistence, curiosity, creativity, and problem solving
  • Language development and communication, which includes listening and understanding, speaking, and literacy
  • Cognitive development, which includes exploration, memory, and play
  • Physical and motor development

The guidelines also explain what adults can do to support children’s optimal learning and development. For example:



EXAMPLES OF CAREGIVER STRATEGIES for promoting problem solving

Young Infant

(Birth to 8 months)

  • Allow baby time to explore and examine objects and new things
  • Watch, but don't interrupt, when baby is busy exploring toys or other objects
  • Occasionally place objects far enough away so baby has to move to get them
  • Offer support and suggestions for problem solving, but do not intervene too quickly
  • Comment positively on baby's attempts and successes in solving problems

Older infant

(6 to 18 months)

  • Allow baby freedom to move and explore how things work and what baby can do with things
  • Provide a variety of interesting action toys that come apart, move and can be used in many ways
  • Allow baby time to play with and explore everyday household objects
  • Show excitement when baby discovers new uses for familiar things, such as putting blocks in a box or pot
  • When baby encounters a problem, offer suggestions and support, but do not intervene too quickly
  • Notice and comment positively when baby solves a new problem or applies knowledge to new situations


(15 to 36 months)

  • Set up the environment to allow new and more complex ways of playing with toys and combining and using materials
  • Allow toddler to choose different activities, times and ways of doing things
  • Allow toddlers to show their creativity and imagination by solving problems in their own ways
  • Ask questions and express wonder about a problem to help toddlers think about and remember how they solved similar problems before
  • Show delight in the accomplishments, new skills and abilities that toddler has developers


More Online Resources About Child Development

  • – the skills and behaviors you can expect from your baby at every stage from birth to 3
  • – more on developmental stages from the American Academy of Pediatrics
  • - developmental milestones checklists from the Centers for Disease Control and Prevention
  • - a child development tracker for insights on the stages of growth, from PBS Parents