1. Evaluating Piaget
Mrs. Hadgraft

2. Bell Ringer

3. Evaluation of the theory
Piaget argued that the best way to teach a child is through child-centered learning: Teachers will set up situations where the child can discover new information for themselves
HOWEVER: Piaget did not clearly explain when each stage takes place
He suggested that children are active in searching out knowledge and constructing mental representations of the world, so these stages may occur at different times

4. Limitations
Methodology: Samples were small and made mainly of his own children - so hard to generalize
Cultural bias
Piaget may have underestimated children’s cognitive abilities

5. Piaget’s Evidence
Piaget did a number of laboratory experiments in which he drew his conclusions from:
Sensorimotor: The blanket and ball study
Preoperational: The Three Mountains Task/ Conservation of Water
Concrete Operational: Conservation of water/ Conservation of numbers
Formal Operational” The pendulum task/ The third eye task

6. Evaluation of the theory
Many theorists argue that the ages Piaget set for each stage are incorrect

7. Sensorimotor Evaluation
There is evidence that object permanence occurs earlier than Piaget claimed. Bower and Wishart (1972) used a lab experiment to study infants aged between 1 – 4 months old.
Instead of using a Piaget’s blanket technique they waited for the infant to reach for an object, and then turned out the lights so that the object was no longer visible. They then filmed the infant using an infra red camera. They found that the infant continued to reach for the object for up to 90 seconds after it became invisible.
Baillargeon 1991:
Showed children a possible event and an impossible event
Children were shown a carrot
In one condition a small carrot was placed behind a wall, and came out the other side, as a small carrot (possible event) the baby did not pay much attention
In the second condition a tall carrot went behind a wall with a window. The carrot disappeared, but then reappeared on the other end. The baby reacted surprised, showing that they understood the carrot was behind the wall, and therefore they should have seen it (Object permanence) The baby was only 3.5 months old

9. Part 2
Ballard did another study in which the child was shown a drawbridge
In one event (possible) an object was placed behind it, and the drawbridge stopped, the child was no surprised
In the second event an object was placed behind the drawbridge and it went through it
The baby acted surprised – again showing object permanence

10. Pre-Operational Evaluation
Hughes Naughty Boy Task 1975
Created an experimental set up with a doll and a policeman
They were placed in an apparatus of two pieces of wood forming a cross
The experimenter then asked the child if the policeman could see the doll
The child was then asked to hide the doll so the policeman could not find it
Nearly all of the children from age could perform the task

11. Spatial orientations vs visualization
Spatial orientation is the ability to understand and operate on relationships between objects in space.
This ability is needed for finding your way in a building
Spatial visualization enables a person to carry out mental movements of two and three-dimensional objects in space.
This is the ability required to do Piaget's three mountains task. Either imagine yourself behind the mountains looking at them, or imagine the mountains themselves rotating around in front of you.

12. Li et al 1999
Tested 486 Chinese elementary school children on classic liquid conversation task
It supports Piaget’s theory the percentage of children who get this question right increases with age
Children from schools with a good academic reputation achieve better results than those from less privilege schools
Related to brain maturation as well as environment

13. Concrete Operational Evaluation
Rose and Blank (1974) argued that when a child gives the wrong answer to a question, we repeat the question in order to hint that their first answer was wrong. This is what Piaget did by asking children the same question twice in the conservation experiments, before and after the transformation.
When Rose and Blank replicated this but asked the question only once, after the liquid had been poured, they found many more six-year-olds gave the correct answer. This shows children can conserve at a younger age than Piaget claimed.

14. McGarrigle and Donaldson (1974):
Another feature of the conservation task which may interfere with children's under-standing is that the adult purposely alters the appearance of something, so the child thinks this alteration is important.
When two identical rows of sweets were laid out and the child was satisfied there were the same number in each, a 'naughty teddy' appeared. While playing around, teddy actually messed up one row of sweets. Once he was safely back in a box the children were asked if there were the same number of sweets.
The children were between four- and six-years-old, and more than half gave the correct answer. This suggests that, once again, Piaget's design prevented the children from showing that they can conserve at a younger age than he claimed.

15. Concrete Operational
Dasen (1994): Different cultures achieve different operations at different ages depending on their cultural context.
Dasen (1994) cites studies he conducted in remote parts of the central Australian desert with 8-14 year old Aborigines.
He gave them conservation of liquid tasks and spatial awareness tasks. He found that the ability to conserve came later in the aboriginal children, between aged 10 and 13 ( as opposed to between 5 and 7, with Piaget’s Swiss sample).
However, he found that spatial awareness abilities developed earlier amongst the Aboriginal children than the Swiss children.
Such a study demonstrates cognitive development is not purely dependent on maturation but on cultural factors too – spatial awareness is crucial for nomadic groups of people.
Greenfield (1966) that schooling influenced the acquisition of such concepts as conservation.