Layer of Necessity Model
By: Martin Tesmer and John F. Wedman (1990)
The Layer of Necessity Instructional Development Model was designed by Martin Tessmer and John F. Wedman. Tesmer is a CITT Director at Colorado University. Wedman was a professor at the University of Missouri teaching the school of information science and learning technology before passing in 2013.
The Layer of Necessity Instructional Development Model was introduced in 1990. The purpose of the Model was to choose a layer of design and incorporate into a project. The simplified the project is, the less amount of layers are used. The more complex the project the more layers are used with the layers that follow are a more detailed description of the layer that it stems from.
Context for Use
In approaching the type of training, the Layer of Necessity gives the educator the choice and materials/ resources. The model goes further in detail instead of adding on the materials that are already understood in your research. The purpose of the Layer of Necessity is to enhance that material and resources already made. As stating in the article, the key to using the Layer of Necessity model lies on time and resources to develop a product (ETR&D, 84)
The advantages that the Layer of Necessity brings is a combination of all Instructional Design models into one simple model. Based on the experience of the person or time, the Layer of Necessity works for all approaches. The Layer of Necessity model is based of personal judgement and not the opinion of others that makes this model and advantage for approaching a topic.
The disadvantages the Layer of Necessity Model may bring is the proper balance of material. In example, since the approaches are based of personal judgement, some content may enter deeper in detail than some areas based on the persons' liking. Experience could also play a factor in a disadvantage that the Layer of Necessity may bring. The reason being people without the proper expertise in certain areas may not be able to allocate resources to complete the project.