22.2 Macro-adaptive instructional systems

Early attempts to adapt the instructional process to individual learners in school education were certainly macrolevel because the students were simply grouped or tracked by grades or scores from ability tests. This homogeneous grouping had minimal effect because the groups seldom received different kinds of instructional treatments (Tennyson, 1975). In the early 1900s, however, a number of adaptive systems were developed to better accommodate different student abilities. As examples, Reiser (1987) described the Burke plan, Dalton plan, and Winnetka plan that were developed in the early 1900s. The main adaptive feature in these plans was that the student was allowed to go through the instructional materials at her or his own pace. The notion of mastery learning was also fostered in Dalton and Winnetka plans (Reiser, 1987).

Since macro-adaptive instruction is frequently used within a class to aid the differentiation of teaching operations over larger segments of instruction, it often involves a repeated sequence of "recitation" activity initiated by teachers' behaviors in classrooms (Como & Snow, 1983). For example, a typical pattern of teaching is: (a) explaining or presenting specific information, (b) asking questions to monitor student learning, and (c) providing appropriate feedback for the student's responses.

Several macro-adaptive instructional systems developed in the 1960s are briefly reviewed below.

22.2.1 Keller Plan

In 1963, Keller and his associates (Keller, 1968, 1974) at Columbia University developed a macro-adaptive system called the Keller plan in which the instructional process was personalized for each student. The program incorporated four unique features: (a) requiring mastery of each unit before moving to the next unit, (b) allowing self-learning pace, (c) using textbooks and workbooks as the primary instructional means, and (d) using student proctors for evaluating student performance and providing feedback. The Keller plan was used at many colleges and universities throughout the world (Reiser, 1987) during the late 1960s and early 1970s.

22.2.2 Audio-Tutorial System

In 1961, the Audio-Tutorial System (Postlethwait, Novak & Murray, 1972) was developed at Purdue University by applying audiovisual media, particularly audiotape. The unique feature of this audio-tutorial approach was a tutorial-like instruction using audiotapes, along with other media like texts, slides, models, etc. This approach was effectively used for teaching college science courses (Postlethwait, 198 1).

22.2.3 PLAN

In 1967, Flanagan and his associates (Flanagan, Shanner, Brudner & Marker, 1975) developed a Program for Learning in Accordance with Needs (PLAN) to provide students with options for selecting different instructional objectives and learning materials. For the selected instructional objective(s), the student needed to study a specific instructional unit and demonstrate the mastery before advancing to the next unit for other objective(s). In the early 1970s, more than 100 elementary schools participated in this program.

22.2.4 Mastery Learning Systems

A popular approach to individualized instruction was developed by Bloom and his associates at the University of Chicago (Block, 1980). In this mastery learning system, virtually every student achieves the given instructional objectives by having sufficient instructional time and materials for her or his learning. "Formative" examination is given to determine whether the student needs more time to master the given unit, and "summative" examination is given to determine mastery. The mastery learning approach was widely used in the United States and several foreign countries. The basic notion of mastery learning, initially proposed by Carroll (1963), is still alive at many schools and other educational institutes. However, the instructional adaptiveness of this mastery learning approach is mostly limited to the "time" variable.

22.2.5 IGE

A more comprehensive macro-adaptive instructional system, called Individually Guided Education (IGE), was developed at the University of Wisconsin in 1965 (Klausmeier, 1975, 1976). In IGE, instructional objectives are first determined for each student based on his or her academicability profile, which includes diagnostic assessments in reading and mathematics, previous achievements, and other aptitude and motivation data. Then, to accommodate different student-learning abilities and styles, the teacher determines necessary guidance for each student, and selects alternative instructional materials (e.g., text, audiovisuals, group activities, etc.) and interactions with other students. The goals and implementation methods of this program could be changed to comply with the school's educational assumptions and institutional traditions (Klausmeier, 1977). However, an evaluation study by Popkewitz, Tabachnick, and Wehlage (1982) reported that the implementation and maintenance of IGE in existing school systems were greatly constrained by the school environments.

22.2.6 IPI

The Individually Prescribed Instructional System (IPI) was developed by the Learning Research and Development Center (LRDC) at the University of Pittsburgh in 1964 to provide students with adaptive instructional environments (Glaser, 1977). In IPI, the student was assigned to an instructional unit within a course according to the student's performance on a placement test given before the instruction. Within the unit, a pretest was given to determine which objectives the student needed to study. Learning materials required to master the instructional objectives were prescribed. After studying each unit, students took a posttest to determine their mastery of the unit. The student was required to master specific objectives for the instructional unit before advancing to the next unit.

22.2.7 ALEM

The LRDC extended IPI with more various types of diagnosis methods, remedial activities, and instructional prescriptions. 'the extended system is called the Adaptive Learning Environments Model (ALEM) (Wang, 1980). The main functions of ALEM include: (a) instructional management for providing learning guidelines on the use of instructional time and resources materials, (b) guidance for parental involvements at home in learning activities provided at school, (c) a procedure for team teaching and group activities, and (d) staff development for training teachers to implement the system (Como & Snow, 1983). An evaluation study (Wang & Walberg, 1983) reported that 96% of teachers were able to establish and maintain the ALEM in teaching economically disadvantaged children (kindergarten through grade 3), and that the degree of its implementation was associated with students' efficient use of learning time and with constructive classroom behaviors and processes.

22.2.8 CMI Systems

Well-designed computer-managed instructional (CMI) systems have functions to diagnose student learning needs and prescribe instructional activities appropriate for the needs. For example, the Plato Learning Management (PLM) System at Control Data Corporation had functions to give a test on different levels of instruction: an instructional module, lesson, course, and curriculum. An instructional module was designed to teach one or more instructional objectives; a lesson consisted of one or more modules; a course consisted of one or more lessons; and a curriculum had one or more courses. The PLM can evaluate each student's performance on the test and provide specific instructional prescriptions. For example, if a student's score has not reached the mastery criterion for a specific instructional objective on the module test, the PLM assigns a learning activity or activities for the student. After studying the learning activities, the student is required to take the test again. When the student demonstrates the mastery of all objectives in the module, the student is allowed to move to the next module. Depending on the instructor or instructional administrator's choice, the student can complete the lesson, course, or curriculum by taking only corresponding module tests, although the student may be required to take additional summary tests on the lesson level, course level, and curriculum level. In either case, this test-evaluation-assignment process is continued until the student demonstrates the mastery of all the objectives, modules, lessons, courses, and curriculum. In addition to the test-evaluation-prescription process, the PLM provides several other features important in adapting instruction to the student's needs and ability: (a) the instructor is allowed to choose appropriate objectives, modules, lessons, and courses in the curriculum for each student to study; (b) the student can decide the sequence of instructional activities by choosing a specific module to study; (c) frequently, more than one learning activity is associated with an instructional objective, and the student has the option to choose which activity or activities to study; and (d) since most learning activities associated with the PLM are instructor-free, the student can choose the time to study it and progress at his or her own pace.

As described above in the PLM functions, well-designed CMI systems provide many important macro-adaptive instructional features. While the value of a CMI system has been well understood, its actual use has been limited due to the need for a central computer system that allows the instructor to monitor and control the student's learning activities at different locations and different times. However, the dramatic increase of personal computer (PC) capability and the simple procedure to make linkages among PCs make it easy to provide a personalized CMI system.

Ross and Morrison (1988) developed a macro-adaptive system combining some of the basic functions of CMI (e.g., prescription of instruction) and some of the features of micro-adaptive models (e.g., prediction of student learning needs). Unlike the PLM, this system was designed primarily for providing adaptive instruction rather than managing the instructional process. However, the student's learning needs are diagnosed only from pre-instructional data, and a new instructional prescription cannot be generated until the next unit of instruction begins. This system consisted of three basic steps: First, variables for predicting the student's performance on the task are selected (e.g., measures of prior knowledge, reading comprehension, locus of control, and anxiety). Second, a predictive equation is developed using multiple regression analysis. Third, instructional prescription (e.g., necessary number of examples estimated to learn the task) was selected based on the student's predicted performance. This system was developed by simplifying a microadaptive model (trajectory/multiple regression approach) described in a later section.

The macro-adaptive instructional programs described above are representative examples that have been instantiated and used in existing educational systems. As mentioned at the beginning of this chapter, macro-adaptive instruction, except for CMI systems, has been a common practice in many school classrooms for a long time, although the adaptive procedures have been mostly unsystematic and primitive with the magnitude of adaptation widely different among teachers. Thus, several different models have been proposed to examine analytically the different levels and methods of adaptive instruction and to provide guidance for developing adaptive instructional programs.