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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