自1976年取得坦普尔大学教育媒体与教育心理学博士学位以来，先后在美国的宾夕法尼亚州立大学、科罗拉多大学、北卡罗纳大学，荷兰的特温特大学，巴西的巴西大学，新家坡的南洋理工大学，挪威的卑尔根大学等世界多所大学任教。 　　发表有27本专著以及大量的文章、论文，其研究领域涉及视觉文化、认知风格、教学设计、基于计算机的学习、超媒体、建构主义、建构主义学习环境以及认知 工具等。最近编辑出版的专著有：《学习环境的理论基础》(2000)、 《学会用技术解决问题：一个建构主义者的观点》(2003)、((教育传播与技术研究手册》(2004)和《学会解决问题：教学设计指南》 (2004)。 　　其目前的研究主要关注认知建模与认知任务分析、问题解决、建构主义学习环境设计、学习中认知工具的开发等。

David H. Jonassen 　　Dr. David H. Jonassen is currently a Distinguished Professor of Education and Director for the Center for the Study of Problem Solving at the University of Missouri-Columbia. He has also taught at The Pennsylvania State University, the University of Colorado at Denver, the University of North Carolina at Greensboro and Temple University. He is probably best known for his work on constructivist learning. His current research focus is in the area of problem solving.

　　1. What led David Jonassen to the field of instructional technology or learning sciences? In an interview conducted in by Instructional Technology Research Online (InTRO, May 1995), David Jonassen described how he came across an ad in the University of Delaware Placement Office (where he received his undergraduate degree in business administration/finance) for a television cameraman. The job paid $1.60/hour, which, for the time, was at the top of the pay scale. He applied, got the job, and spent three years at the university working in instructional television, doing a variety of tasks: directing, production, running the camera, engineering and lighting. After that experience, he said that he knew that he wanted to become involved in "educational media" and continued to build a foundation toward that end (InTro, May 1995). He earned a master's degree in elementary education (trying out several instructional systems), taught in a couple of public schools and then started a doctoral degree at Temple University, ultimately earning an Ed.D. in 1976 in educational media/educational psychology (Jonassen, 2010). He is now considered one of the leading experts in the field of instructional technology.
　　2. Where was the entrance of David Jonassen into the field situated in the historical development of the field?
　　Interestingly enough, David Jonassen's entry into the instructional design field was immediately following his time spent in the late 60s at the University of Delaware as a television cameraman filming for instructional television. After the three-year stint filming videos, Jonassen felt compelled to enter the instructional design field, specifically in "educational media." Teaching with television as a medium was a rapidly expanding and developing field. For his Ed.D., he completed his dissertation on the topic Videotape Interaction with the Self: Effects of Self-Confrontation as a Function of Extraversion and Neuroticism in College Students (Jonassen, 2010). Jonassen apparently possessed a very strong interest to find out more about how media technology was affecting the instruction and teaching processes exploring the older psychological theory of objectivism versus the newer theory of constructivism.
　　The computer era developed and expanded into the instructional design field shortly after television was used for education and was a logical next step in the progression. Jonassen was directly involved in computer programs being specifically designed for learning and education among many other uses. This exposure, plus an increased world emphasis in globalization of businesses and education at this time, created opportunities for expansion into never before conceptualized ideas for instructional design research for those actively engaged in the field, which Jonassen was and still is at the present time.
　　Other prominent psychological research developments of Jonassen's time period greatly affected his work and helped set the historical context. Individuals such as Lev Vygotsky and his work on sociohistorical development psychology and theory of the zone of proximal development resulting from an individual's social interaction developed into constructivist teaching (Vygotsky, n.d.). Other prevalent theory at the time included Bruner's construction theory that "learning is an active process in which learners construct new ideas or concepts based upon their current/past knowledge" (Bruner, n.d.).
　　3. What are two major ideas/models of Dr. Jonassen? Please explain these ideas/models.
　　Model one: Mindtools
　　Jonassen argued that traditional means of knowledge assessment only used one type of solving method which required less cognitive skills. For example, students who can solve math problems using formulas could not apply those same formulas to real-world or scenario based problems. The students relied too much on the memorization of the formula and not on learning the concepts that would help them apply their problem solving skills in the real world. Jonassen theorized that computer technology could help students represent what they are learning in different ways. He called computers mindtools and defined it as knowledge construction tools used to learn with not from (Chad & Jonassen, 2000). This way the student is in complete control of their learning environment. They design, organize and interpret their own personal knowledge. Below are some of the mindtools he gives as examples:
　　◆ Databases: Allow the student to use simple to complex queries to solve problems. This helps a student develop critical thinking skills as they construct their queries to get the appropriate dataset. Sometimes the database can be populated by the students themselves and gives them a chance to exercise their cognitive skills in collecting data that must conform to whatever data structure they filling. vThis knowledge base is an example of a database mindtool.
　　◆ Semantic mapping (concept mapping): Students construct visual maps of related concepts connected together by lines as a study tool. Programs such as Microsoft Visio, Omnigraffle or VUE from Tufts University can help students create concept maps. These maps allow a student to identify the important concepts and connect those together as well as label the relationship they have with one another. Semantic mapping allows students to deeply process the knowledge they have learned by allowing them relate, reorganize and describe the information contained in a map.
　　◆ Spreadsheets: Allow the student to perform what-if scenarios by changing values in one cell and having the changes cascade throughout the related cells. Students use spreadsheets to consider the implications of certain conditions or options and speculate and hypothesize about outcomes (Carr & Jonassen, 2000). Using spreadsheets also allows students to represent their knowledge as mathematical formulas and phenomena.
　　Model two: Instructional design models for well-structured and ill-structured problem-solving learning outcomes
　　According to Dr. Jonassen, there are three kinds of problems: puzzle problems, well-structured problems and ill-structured problems. Puzzle problems are well-structured with a single correct answer where all elements required for the solution are known and solutions require using logical, algorithmic processes (Kitchner, 1983). Well-structured application problems require the application of a finite number of concepts, rules and principles being studied to a constrained problem situation. Ill-structured problems are typically emergent dilemmas that are encountered in everyday practice. They are ill-defined (Wood, 1983), have unclear goals and unstated constraints (Voss, 1988), process multiple solutions or no solution at all (Kichner, 1983), have multiple criteria, have less manipulative parameters and have no prototypic cases. In a word, the concepts, rules and principles required in ill-structured problems are uncertain, inconsistent and ill-defined (Jonassen, 1997).
　　◆ An instructional design model for well-structured problems.
　　o Problem solving process for well-structured problems.
　　§ Step 1: Problem representation
　　§ Step 2: Search for solutions. This step includes means-ends analysis, decomposing and simplifying and generate~test. Means-ends analysis involves reducing the discrepancy between the current state and the goal state of the problem by applying problem-solving operators (Gick, 1986). Decomposing and simplifying involves finding sub-goals. Generate~test evaluates for the potential to solve the problem.
　　§ Step 3: Implement solutions.
　　o Designing and developing well-structured problem-solving instruction.
　　§ Step 1: Review prerequisite component concepts, rules, and principles. Solving well-structured problems requires learners to identify, select, and apply relevant domain information.
　　§ Step 2: Present conceptual or causal model of problem domain.
　　§ Step 3: Model problem solving performance in worked examples. Worked examples can help learners to construct useful problem schemas.
　　§ Step 4: Present practice problems.
　　§ Step 5: Support the search for solutions.
　　§ Step 6: Reflect on problem state and problem solution.
　　◆ An instructional design model for ill-structured problems.
　　o Process for solving ill-structured problems.
　　§ Step 1: Learners articulate problem space and contextual constraints. Ill-structured problems depend on domain or context because they require the problem solver to think about the problems as realistic situations (Bransford, 1994).
　　§ Step 2: Identify and clarify alternative opinions, positions and perspectives of stakeholders.
　　§ Step 3: Generate possible problem solutions.
　　§ Step 4: Assess the viability of alternative solutions by constructing arguments and articulating personal Beliefs.
　　§ Step 5: Monitor the problem space and solution options.
　　§ Step 6: Implement and monitor the solution.
　　§ Step 7: Adapt the solution. Few problems are solved in only a single attempt. Problem solvers recommend a solution and then adjust and adapt it based on feedback.
　　o Designing and developing ill-structured problem-solving instruction.
　　§ Step 1: Articulate problem context.
　　§ Step 2: Introduce problem constraints.
　　§ Step 3: Locate, select and develop cases for learners.
　　§ Step 4: Support knowledge base construction.
　　§ Step 5: Support argument construction. The argument will provide the best evidence for domain knowledge that they have acquired.
　　4. What is the influence of the ideas/models on current thought in instructional technology/learning sciences? Were the ideas fully understood as Dr. Jonassen originally intended?
　　It is useful to examine both the opinion of Dr. Jonassen on the subject and those of a researcher following his work.
　　In an interview conducted by Daniel Oswald, Dr. Jonassen was asked which of his contributions to the field did he "believe to be most significant" (Oswald, n.d.). In his answer, he cited the publication of his article, "Objectivism vs. Constructivism: Do We Need a New Paradigm?" in Educational Technology Research and Development. He also spoke of the two issues on constructivism that he co-edited for Educational Technology. He described these publications as perhaps having been the catalyst for change that was occurring in the field of instructional technology at that time, apparently feeling that his ideas were taken as he intended (Oswald, n.d.).
　　At the same time, there is room for ambiguity. In the same interview, Dr. Jonassen stated, "There really isn't one current direction of the field. There are multiple directions; there is no unified theory" (Oswald, n.d.). The adherents of differing philosophies within the field may subscribe in part to Dr. Jonassen's models but interpret them in a number of ways, along with the influence of other contributors.
　　One example of the interpretation and influence of Dr. Jonassen's work is an article titled Theory into Practice: Applying David Jonassen's Work in Instructional Design to Instruction Programs in Academic Libraries by Alexius Smith Macklin. This article applies Dr. Jonassen's theories on problem-solving in terms similar to his own. He states, "Although these problem types have been described above as discrete classes, in reality, most problems constitute variations or hybrids of these classes....We do not presume to have articulated discrete, predictable forms of problem-solving activity" (Jonassen, n.d.). Macklin in turn writes that, "Jonassen claims that problem-solving skills are the most difficult to teach because we do not understand these activities well enough to support them. He further states that every problem has two critical attributes. The first is an unknown entity in a given situation. The second is some social, cultural, or intellectual value in the unknown" (Macklin, 2003). This would reflect Dr. Jonassen's acknowledgement that problem-solving is an issue with many factors that cannot always be codified.
　　While Dr. Jonassen's attitudes toward problem-solving are not necessarily ambiguous, they take into account and leave room for the unknown factors of human involvement. "If we believe that the cognitive requirements of solving different kinds of problems varies, then so too must the nature of instruction that we use to support the development of problem-solving skills. Why? Among the most fundamental beliefs of instructional design is that different learning outcomes require different instructional conditions" (Jonassen, n.d.).
　　Macklin cites Dr. Jonassen's creation of cognitive learning environments (CLEs) and lists specific steps for creating instruction (Macklin, 2003). However, he seems to understand that, a concrete list of design elements aside, this unknown factor does exist. The many different types of problems extant require instructional designers to mold their instruction accordingly (Macklin, 2003). This assessment seems to adhere closely to Dr. Jonassen's original intentions.
　　REFERENCES
　　Bruner, J. (n.d.). Constructivist theory. Retrieved from http://tip.psychology.org/bruner.html
　　Carr, C. S., & Jonassen, D. H. (2000). Mindtools: Affording multiple knowledge representations for learning. In S.P. Lajoie (Ed.), Computers as cognitive tools, Volume 2: No more walls. (165-195). Mahwah, NJ: Lawrence Erlbaum Associates. Retrieved from http://web.missouri.edu/jonassend/Mindtoolschapter.pdf
　　Jonassen (Interviewee). (May, 1995). Instructional Technology Research Online (InTRO) [Interview transcript]. Retrieved from http://www2.gsu.edu/～wwwitr/features/leaders/jonassen.html
　　Jonassen, D. (1997). Instructional design models for well-structured and ill-structured problem-solving learning outcomes. Educational Technology Research and Development, 45(1), 65-94. Retrieved from ERIC database. Jonassen, D. (2010). Curriculum vitae. Retrieved from http://web.missouri.edu/jonassend/CV-JONASSEN.pdf
　　Jonassen, D. (2010). Biography. Retrieved from http://www.asee.org/documents/conferences/annual/2010/Jonassen-bio_000.pdf
　　Jonassen, D. (n.d.). Research on problem solving. Retrieved from http://web.missouri.edu/jonassend/PB.html
　　Jonassen, D. (n.d.). Toward a meta-theory of problem solving. Retrieved from http://web.missouri.edu/jonassend/problems.htm
　　Macklin, A. S. (2003). Theory into practice: applying David Jonassen's work in instructional design to instruction programs in academic libraries. College & Research Libraries, v. 64(6), 494-500.
　　Oswald, D. F. (September/October 2003). A conversation with David Jonassen. Educational Technology.Retrieved from http://web.missouri.edu/jonassend/interviews.html
　　Vygotsky, L. (n.d.). Social development theory. Retrieved from http://tip.psychology.org/vygotsky.html