Early Intervention Special Education: Birth to Age Five Services

The first years of a child’s life are a period of remarkable brain development, with neural connections forming at a rate of more than one million per second. Early intervention services capitalize on this neuroplasticity to address developmental delays and disabilities during the window when intervention has the greatest impact. IDEA provides two programs for young children: Part C for infants and toddlers birth through age two, and Section 619 of Part B for preschool children ages three through five. Understanding these programs helps families access critical early services that can shape their child’s developmental trajectory.

The Case for Early Intervention

The research supporting early intervention is overwhelming. The brain is most adaptable early in life, and early intervention can: prevent or minimize the impact of developmental delays, reduce the need for more intensive services later in life, improve cognitive and academic outcomes, enhance social-emotional development and family relationships, and produce significant cost savings over the lifespan.

The Centers for Disease Control and Prevention estimates that 1 in 6 children aged 3 to 17 has a developmental disability. Yet many children are not identified until they enter school and fall behind their peers. Early identification through screening and surveillance — combined with prompt referral to early intervention services — can close this gap.

Part C: Infants and Toddlers (Birth to Age Three)

IDEA Part C provides early intervention services for infants and toddlers with developmental delays or diagnosed conditions that have a high probability of resulting in developmental delay. Services are designed to meet the developmental needs of the child and the needs of the family related to enhancing the child’s development.

Eligibility criteria. Each state defines developmental delay differently, but typically eligibility requires a 25 to 33 percent delay in one or more developmental areas: cognitive development, physical development (including vision and hearing), communication development, social or emotional development, or adaptive development. Children with diagnosed conditions like Down syndrome, cerebral palsy, autism spectrum disorder, or significant hearing or vision loss are automatically eligible regardless of documented delay.

The Individualized Family Service Plan (IFSP). Unlike the IEP, which focuses on the child in educational settings, the IFSP focuses on the child and family in natural environments. The IFSP is developed by a team that includes the family, early intervention specialists, service coordinators, and other professionals. It includes:

• Information about the child’s present levels of development
• Family resources, priorities, and concerns related to enhancing the child’s development
• Measurable outcomes for the child and family
• Early intervention services, including frequency, intensity, method, and location
• Natural environments statement justifying any services not provided in natural settings
• Service coordinator designation
• Transition plan for moving to preschool services at age three

Natural environments. Part C requires that services be provided in natural environments — settings where children without disabilities would typically be found — to the maximum extent appropriate. This includes the child’s home, child care centers, parks, and other community settings.

Service coordination. Each family is assigned a service coordinator who helps them navigate the early intervention system, coordinate services, and access community resources. The service coordinator is the family’s single point of contact throughout the Part C process.

Early intervention services. Part C services include: assistive technology, audiology and hearing services, family training and counseling, health services (for diagnostic and evaluation purposes), medical services (for diagnostic and evaluation purposes), nursing services, nutrition services, occupational therapy, physical therapy, psychological services, service coordination, sign language and cued language services, social work services, speech-language pathology, transportation and related costs, and vision services.

Screening and Surveillance

Early identification of developmental delays begins with screening. The American Academy of Pediatrics recommends developmental screening at 9, 18, and 30 months of age, plus autism-specific screening at 18 and 24 months. Screening tools like the Ages and Stages Questionnaire (ASQ) and the Modified Checklist for Autism in Toddlers (M-CHAT) are quick, validated instruments that identify children who need further evaluation.

Child Find is a federal requirement under IDEA that mandates each state locate, identify, and evaluate all children with disabilities from birth through age 21. Child Find activities include public awareness campaigns, screening events at health fairs and preschools, and partnerships with pediatricians and childcare providers. Parents who suspect their child has a developmental delay can contact their local Child Find program directly, even without a physician referral.

Regular developmental surveillance — monitoring development at every healthcare visit — complements formal screening. Parents are often the first to notice that their child is not meeting milestones. Concerns such as “my child is not babbling,” “my toddler does not point at things,” or “my preschooler does not play with other children” should always be taken seriously and should prompt referral for evaluation without delay.

Transition from Part C to Part B

The transition from Part C to preschool special education (Part B, Section 619) occurs when the child turns three. This transition is a critical juncture that requires careful planning:

Transition planning meeting. The IFSP team must hold a transition planning meeting at least 90 days before the child’s third birthday. The meeting addresses the child’s current status, options for preschool services, and steps for a smooth transition.

Eligibility determination. Part B preschool services have different eligibility criteria than Part C. Not all children who qualify for Part C will qualify for Part B. The school district must conduct an evaluation to determine eligibility for preschool special education.

Option for continued Part C services. Some states allow children who turn three during the summer to continue Part C services until the beginning of the school year, preventing a gap in services during the transition.

Preschool Special Education (Ages Three to Five)

Part B, Section 619 of IDEA provides special education and related services for preschool-aged children with disabilities. Services are typically provided through the public school system.

IEP development. Preschool children receive an IEP rather than an IFSP. The IEP includes many of the same components used for school-aged students — present levels, annual goals, special education services, accommodations, and placement — but the content is developmentally appropriate for young children.

Preschool placement options. Services can be provided in various settings including: regular preschool or child care with itinerant services, inclusive preschool classrooms staffed by both general and special education teachers, self-contained special education preschool classrooms, home-based services, and community-based settings.

Least restrictive environment for preschoolers. IDEA requires that preschool children with disabilities be educated with typically developing peers to the maximum extent appropriate. Schools must provide a continuum of placement options and cannot place all children with disabilities in a segregated preschool class by default.

The Role of Families in Early Intervention

Early intervention is fundamentally a family-centered endeavor. Parents are not passive recipients of services — they are active partners in assessment, planning, and implementation.

Family assessment. The IFSP process includes identifying family resources, priorities, and concerns. This is not an evaluation of the family but an opportunity for families to express what they need to support their child’s development.

Parent-implemented intervention. Many early intervention strategies are designed to be implemented by parents during daily routines — feeding, bathing, dressing, playing. The early interventionist coaches the parent, who then uses the strategies throughout the day, maximizing the amount of intervention the child receives.

Parent rights in early intervention. Part C provides procedural safeguards including: prior written notice before changes in services, informed written consent for evaluation and services, access to records, the right to decline services, dispute resolution including mediation and due process, and confidentiality protections.

Research Supporting Early Intervention

The scientific evidence for early intervention is compelling. The landmark Abecedarian Project, a randomized controlled trial beginning in the 1970s, found that children who received high-quality early intervention from infancy through age five had significantly higher cognitive and academic outcomes through age 21 compared to controls. More recent research has refined our understanding of which interventions work best and for whom.

Neuroscience explains why early intervention is so effective. During the first three years of life, the brain produces far more synapses than it will eventually keep. Synapses that are used are strengthened; those that are not are pruned away. This period of heightened plasticity means that intervention during early childhood can literally shape brain architecture, building stronger neural pathways for communication, cognition, and social-emotional functioning.

Specific interventions with strong research support include: the Early Start Denver Model (ESDM) for toddlers with autism, which improved IQ, language, and adaptive behavior in a randomized controlled trial published in Pediatrics; parent-implemented language interventions for late-talking toddlers; and physical therapy programs for children with motor delays. Research consistently finds that the intensity and quality of intervention matter — more hours of well-implemented intervention produce better outcomes.

Frequently Asked Questions

How do I refer my child for early intervention services? Parents can call their state or local early intervention program directly. Pediatricians, child care providers, and other professionals can also make referrals. In most states, the program is called “Early Intervention” or “Birth to Three” and is administered through the state health or education department.

Are early intervention services free? Part C allows states to use a system of payments, including family cost participation, for some services. However, services cannot be denied due to inability to pay. Part B preschool services are provided at no cost to families, just like services for school-aged students.

**What if my child was born prematurely? Premature infants are at higher risk for developmental delays and should be monitored closely. Some states automatically qualify children born before 32 weeks for Part C services. Others require documented delay. Parents of premature infants should request an evaluation if they have concerns.

Conclusion

Early intervention special education provides critical services during the years when the developing brain is most responsive to intervention. Part C services for infants and toddlers and Part B preschool services for children ages three through five give families the tools and supports they need to help their children develop to their full potential. The earlier developmental concerns are identified and addressed, the better the outcomes. For families navigating these systems, understanding the IFSP and IEP processes, knowing their rights, and actively participating in their child’s services are essential steps. For more on the IEP process for older children, see our IEP process guide. For information on supporting children with specific developmental conditions, explore our guides on autism classroom strategies and speech-language therapy.