國內發展電腦輔助教學（CAI）多以教導型（tutorials）為主。教導型的CAI是直接將課程電腦化，它不同於練習式（drill & practice）的CAI，練習式的CAI的反覆地練習教材，以達到熟練的程度。而教導型的CAI能幫助學生學習新的課程。此外依程式控制的策略，教導型的CAI又可分為兩種類別，分別是線性式和分歧式。線性式是最簡單的方法，整個教材被分成許多小單元，學生必須精熟學習一個單元後，才能進行下一個單元的學習，而其教導的順序是由程式設計者決定。至於分歧式的方法則較有彈性，教導的順序由學生的表現或學生自己的選擇來決定。
這些傳統式的CAT的缺點，就是控制單元與教學內容不能分離，造成往後修改的困難。且不能達到真正的個別化教學，也就是當學生在操作系統時，必須自己利用HELP來補足他的需求。
故本研究以國中數學方程式為教材，提出了案例式（case）的方法。這種方法引用了人工智慧的一個技巧概念，稱為Case - Based Planning，以作為發系統的基礎。以下乃為案例式教導型CAI系統的特點。
一、課程的教導是依據一個計畫（plan）來進行，將學生的需求視為一個案例，以不同的教導計畫來教導不同的學生，故能達到個別化教學的目的。
二、教導系統具有修正教導計畫的能力，因此學生不會只受限於預先設計好的教導計畫。
三、程式的控制單元和教材是分開的，如此方便於往後教材內容的修改。
四、為了配合案例式的方法與控制單元和教材分開之目的，以物件導向設計的觀念來設計課程與教材。
案例式的教導法是將學生的需求視為一個案例，教導系統安排一個適當的計畫來教導學生。整個系統設計的重點，乃在於如何從案例資料庫（case base）裡選取教導計畫，如何修正一個教導計畫，以及課程如何呈現。
為了解學生使用本系統的態度，選取了三十位國中二所級的學生作為受試者，由測試後的結果得知，大部分的受試者皆滿意案例式的教導法，亦即本研究提出的案例式教導控制策略能被學生所接受。唯由於本系統是以專家系統工具來製作，缺乏設計圖形介面的功能，故教材內容的呈現不夠生動且不夠活潑，這是需要改進的部分。

As to the domestic development of computer - assisted instruction (CAI), the tutorial is the primary mode of CAI. Lessons are directly computerized into the tutorial program. A tutorial program is not like the drill & practice program which only helps a student refine performace. It is able to teach a student to learn something new. Besides, as far as the program control strategy is concerned, tutorials are divided into two models: linear and branching. The linear model is the simplest way to design the courseware. The instructional materials are arranged into small units. The student must master the current unit and anwer at least a question before proceeding to the next. The sequence of instruction in the linear model is determined by the programmer. By following the sequence, the student accomlishes the learning. The branching model provides flexibility to randomly access lesson units or to make multiple choices. The sequence of instruction is determined by the studetn's performance or choice. That is, branching may occur based on the student's reaction to the tutorial program.
This study proposes a tutorial model called case - based tutorial which incorporates the concepts of a AI technique case - based planning for representing the curriculum of a CAI system. The curriculum is the domain of mathematic equations (linear equations and quadratic equations). The following are some characteristics of CBT (Case - Based Tutorial):
1. CBT regards a student's needs as a case. Instruction is conducted according to a certain plan. Thus, learning and instruction are individualized. CBT provides appropriate course units and the sequence of instruction for the student by a plan.
2. CBT possesses the ability to modify instructional plans. Consequently, students are not limited to receive programmed plans.
3. The program control unit and instructional materials are two separated portions. That makes the instructional materials changeable in order to meet special groups of students.
4. The object - oriented curriculum representation can facilitate the planning process of CBT. And the tutor may use the object - oriented curriculum representation to estalish effective organization of instructional mater ials.
CBT regards a student's needs as a case. It arranges an appropriate plan to teach the student. The design of the case - based tutorial focus on the retrieval of plans from the case base, the modification of plans, and the curriculum representation.
In order to realize student attitude on using the system, there were 30 second graders at the junior high schools selected as subjects. Most of the subjects liked the tutorial method of CBT. The most obvious weakness is that the presentation of course content is not so colorful and active because that the expert system language adopted in this study lacks some functions of designing the graphic user interface. Anyway, the new program control strategy provides a idea of designing a CAI system.