Michael Hast

Towards a Complete Commonsense Theory of Motion: The interaction of dimensions in children's predictions of natural object motion

Events involving motion in fall are differentiated psychologically from events involving horizontal motion. Do children associate motion down inclines more with motion along horizontals or more with motion in fall, or do they even treat it as an integration of the two? The question was raised over 20 years ago but never satisfactorily answered, so the principal aim of the reported research was to take matters forward. Children (n = 144) aged 5–11 years were assessed while predicting natural dynamic events along a horizontal, in fall and down an incline. They were required to make predictions of speed with heavy and light balls and under changes in incline heights. The results show that, consistent with previous work, faster horizontal motion was associated with the light ball across all ages, whereas faster fall was associated with the heavy ball. However, while the younger children predicted faster incline motion for the lighter ball, there was a shift in this conception towards older children predicting faster motion for the heavier ball. Understanding of how changes in incline height affect speed was generally good, with this aspect of the study helping to establish how children perceive diagonal dimensions. How supported horizontal motion and unsupported fall motion may affect childrens changing understanding of incline motion is discussed, thus providing more complete insight into childrens understanding of natural object motion than has been established so far.

Understanding the beliefs informing children’s commonsense theories of motion: the role of everyday object variables in dynamic event predictions

Background Children are not blank slates when they begin school; they bring prior conceptions about the everyday world with them. These conceptions usually do not comply with accepted scientific views and have to be changed within the process of education. However, to do this effectively more needs to be known about the relationship between the everyday world and children’s knowledge of scientific principles. Purpose This study sought answers to the question of which object variables children use when reasoning, and how these variables are associated with outcomes. The reported study addresses these issues in relation to object motion. Sample, design and methods UK primary school children (n = 144) aged 5–11 years were assessed on their predictions of motion along a horizontal, in fall and down an incline using a range of everyday objects by responding to questions where they needed to compare potential motion patterns of the objects. Results Round shape and smooth texture of objects were consistently associated with faster motion across age groups as well as across motion dimensions. However, faster horizontal motion was associated with lighter and smaller objects across all ages, whereas faster fall was associated with heavier objects. While younger children predicted faster incline motion for lighter and smaller objects, there was a shift in conceptions with age, with older children predicting faster motion for heavier and bigger objects. Conclusions The overall findings are used to support the development of commonsense theories of motion previously identified, and suggestions for educational practice are made. Specifically, it is suggested that these findings may need to be taken into consideration in the development of teacher training programmes.