Child Psychology & Development Stages
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Child Development Stages - Complete Guide
1. Prenatal Period (Conception to Birth):
• Germinal Stage (0-2 weeks): Fertilization, zygote formation, implantation
• Embryonic Stage (2-8 weeks): Major organs form, most critical period
• Fetal Stage (8 weeks-birth): Rapid growth, organ refinement
• Teratogens (harmful substances) can cause birth defects
2. Infancy (0-2 years):
Physical Development:
• Birth weight doubles by 5 months, triples by 1 year
• Height increases by 50% in first year
• Reflexes: rooting, sucking, grasping, Moro reflex
• Motor milestones:
- 3 months: Head control
- 6 months: Sitting without support
- 9 months: Crawling
- 12 months: Walking with support
- 15-18 months: Independent walking
Cognitive Development (Sensorimotor Stage - Piaget):
• Object permanence develops (8-12 months)
• Primary circular reactions (1-4 months): Repetition of own actions
• Secondary circular reactions (4-8 months): Actions on environment
• Coordination of secondary schemes (8-12 months): Goal-directed behavior
• Tertiary circular reactions (12-18 months): Experimentation
• Mental representation (18-24 months): Internal thought begins
Language Development:
• 0-2 months: Crying, cooing
• 3-6 months: Babbling (ba-ba, ma-ma)
• 6-12 months: First words (mama, dada)
• 12-18 months: 10-50 words, single-word utterances
• 18-24 months: Two-word phrases, vocabulary explosion
Social-Emotional Development:
• Attachment to primary caregivers (Bowlby)
• Stranger anxiety (6-9 months)
• Separation anxiety (8-15 months)
• Erikson Stage 1: Trust vs Mistrust
3. Early Childhood (2-6 years) - Preschool:
Physical Development:
• Fine motor skills: Drawing, buttoning, using scissors
• Gross motor skills: Running, jumping, climbing
• Toilet training typically occurs
• Handedness (left/right) established
Cognitive Development (Preoperational Stage - Piaget):
• Symbolic thinking: Use of language, pretend play
• Egocentrism: Difficulty seeing others' perspectives
• Centration: Focus on one aspect, ignore others
• Lack of conservation: Don't understand quantity stays same
• Animism: Belief that inanimate objects have life
• Irreversibility: Can't mentally reverse operations
Language Development:
• Vocabulary: 200-300 words at 2 years, 2000+ by 6 years
• Sentence length increases
• Overregularization: "goed" instead of "went"
• Asking "why" questions constantly
Social-Emotional Development:
• Parallel play (2-3 years): Play near but not with others
• Associative play (3-4 years): Shared activities
• Cooperative play (4-6 years): Organized games with rules
• Erikson Stage 2: Autonomy vs Shame & Doubt (1-3 years)
• Erikson Stage 3: Initiative vs Guilt (3-6 years)
• Gender identity develops
• Temper tantrums common
4. Middle Childhood (6-12 years) - School Age:
REET Level 1 Focus Age Group
Physical Development:
• Slow, steady growth
• Fine motor skills refined: Writing, drawing details
• Gross motor skills: Sports, dancing, coordinated movements
• Loss of baby teeth, permanent teeth appear
• Better coordination, balance, reaction time
Cognitive Development (Concrete Operational Stage - Piaget):
• Conservation develops: Understanding quantity doesn't change with appearance
- Number conservation: Age 6-7
- Mass conservation: Age 7-8
- Weight conservation: Age 8-9
- Volume conservation: Age 9-10 • Classification: Can group objects by multiple attributes • Seriation: Can arrange objects in order (size, weight) • Reversibility: Can mentally reverse operations • Decentration: Can consider multiple aspects • Logical thinking about concrete objects and events • Cannot think abstractly yet
Language Development:
• Vocabulary: 8000-14000 words
• Grammar mostly mastered
• Reading and writing skills develop
• Metalinguistic awareness: Thinking about language
• Can understand metaphors and jokes
Social-Emotional Development:
• Peer relationships become important
• Friendships based on common interests, activities
• Erikson Stage 4: Industry vs Inferiority
- Success leads to competence and confidence
- Failure leads to inferiority and inadequacy • Self-concept develops (how child sees self) • Self-esteem influenced by academic performance • Rules and fairness important • Gender segregation in play
Moral Development (Kohlberg - Conventional Level):
• Stage 3: Good interpersonal relationships
• Stage 4: Maintaining social order
Academic Skills:
• Reading fluency improves
• Math concepts: Addition, subtraction, multiplication, division
• Problem-solving strategies develop
• Study habits begin
5. Adolescence (12-18 years):
Physical Development:
• Puberty begins
• Growth spurt
• Primary and secondary sexual characteristics develop
• Brain development continues (especially prefrontal cortex)
Cognitive Development (Formal Operational Stage - Piaget):
• Abstract thinking develops
• Hypothetical-deductive reasoning
• Metacognition: Thinking about thinking
• Can consider multiple perspectives
Development Domains - Detailed:
1. Physical Development:
• Gross motor skills: Large muscle movements (walking, running)
• Fine motor skills: Small muscle movements (writing, cutting)
• Brain development: Myelination, synaptic pruning
• Sensory development: Vision, hearing, touch, taste, smell
2. Cognitive Development:
• Memory: Working memory, long-term memory
• Attention: Selective attention, sustained attention
• Problem-solving: Trial and error, insight, strategies
• Metacognition: Awareness of own thinking
• Executive functions: Planning, inhibition, working memory
3. Language Development:
• Receptive language: Understanding spoken/written language
• Expressive language: Producing language
• Phonology: Sound system
• Syntax: Grammar rules
• Semantics: Word meanings
• Pragmatics: Social use of language
4. Social-Emotional Development:
• Self-concept: How child sees self
• Self-esteem: How child values self
• Identity formation
• Peer relationships
• Attachment: Secure, insecure-avoidant, insecure-resistant, disorganized
• Emotional regulation: Managing emotions
5. Moral Development:
• Kohlberg's stages of moral reasoning
• Empathy development
• Prosocial behavior
Principles of Development:
• Cephalocaudal: Head to toe development
• Proximodistal: Center to periphery (trunk to limbs)
• Simple to complex: Basic skills before advanced
• General to specific: Broad responses to specific
• Continuous: Gradual, ongoing process
• Sequential: Predictable order
• Individual differences: Rate and timing vary
• Interrelated: All domains connected
• Spiral Advancement: Development is not linear; children advance, consolidate, then move forward
Factors Influencing Development:
• Heredity (Nature): Genetic factors, determines limits/potential
• Environment (Nurture): Family, school, community, culture
• Woodworth's Formula: Development = Heredity × Environment
• Nutrition: Critical for physical and cognitive development
• Health: Illnesses, disabilities
• Socioeconomic status: Resources, opportunities
• Education: School quality, parent involvement
• Culture: Values, practices, expectations
Educational Implications:
• Understand developmental stage
• Provide age-appropriate activities
• Respect individual differences
• Create supportive environment
• Scaffold learning
• Use concrete materials for concrete operational stage
• Encourage active learning
• Build on prior knowledge
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