Trends in children's concepts of vertebrate and invertebrate

Children link backbones with movement but see them as large and inflexible. These and other findings are used to argue for a better understanding of structure and function School children's ability to classify animals as vertebrate or invertebrate has been found in previous studies to be weak. Typically vertebrates are regarded as large animals with obvious heads and limbs whilst invertebrates are seen as shapeless, legless animals that crawl. Little is known about the conceptions held by primary aged children or about the ways in which ideas vary with age. This paper reports the results of a cross-age study carried out with children aged between 7 and 15. Children's classification of photographic examples of animals and the attributes of vertebrates and invertebrates they associate with examples have been analysed so that trends in thinking can be shown. The youngest children seem preoccupied with shape, form, and size. A very strong idea held by children at all ages is that any animal that coils or flexes cannot possess a backbone. Children also seem to regard a backbone as a wide, straight structure. Many of the minority of children who classify animals like a snake, seal, and fish correctly as vertebrates seem to have some first-hand experience of internal structure. The paper uses the trends identified to suggest a number of experiences that could be included in the school science curriculum to redress the situation and argues for more classroom work relating structure with function.