以合作方式学习样例的研究
摘要
通过设置对照组的方法，比较合作学习与传统学习这两种学习方式对样例学习效果的影响，并通过分析合作学习过程中的对话，考察合作学习样例的过程和机制。研究结果表明：
1、从总体上来看，合作学习班和传统授课班的学生在近迁移和远迁移问题上的成绩都存在显著差异。合作学习的方式优于传统方式。
2、在近迁移问题上，合作学习班和传统授课班的好生之间不存在显著差异，中等生之间也不存在显著差异；而差生之间差异显著，合作学习样例的方式更有效。
3、在远迁移问题上，合作学习班和传统授课班的中等生之间不存在显著差异，差生之间也不存在显著差异；而好生之间差异显著，合作学习样例的方式更有效。
4、引发学生产生应答行为的话语(即合作性话语)贯穿了合作学习样例的整个过程，而且绝大多数由合作小组的组长产生。
5、合作性话语引发的行为可以大致分为五类，即寻找信息，交流答案、交流解题过程及原理、思考、联系旧知识。其中能引发第三、第四类行为的话语占了总数的70％。
6、前两类合作性话语引发的行为没有生成新的观念；后三类合作性话语促使学生对样例进行深入加工，从而生成新的意义和观念并形成完善的理解，这三类话语是导致合作学习方式优于个体单独学习的根本原因所在。
7、小组成员回答不出讨论中的提问是合作学习中常见的一种现象，这能促使成员对样例进行深加工，并有助于及早发现和弥补知识缺陷。
8、成员的个性特征影响了他们参与合作讨论的主动性，长期磨合使组长有意识地均衡成员的参与。
In this study, the effects of two learning-from-example styles , cooperative learning and traditional learning, on problem solving were examined. In order to discover the process and mechanism of learning-from-example in a cooperative way the conversations videotaped in cooperative learning were also analyzed . The results have shown:
1. As a whole, cooperative and traditional learning styles lead to significant performance difference on both near-transfer and far-transfer problems. Cooperative learning style produces better performance than the traditional one does.
2. On near-transfer problems, there is no significant performance difference in the groups of above-average and average students respectfully in experiment and control conditions. However, for below-average students cooperative learning-from-example is more effective.
3. On far-transfer problems, there is no significant performance difference in the groups of average and below-average students respectfully in experiment and control conditions. However, for above-average students cooperative learning-from-example is more effective.
4. Cooperative arguments which lead to responses from members play a critic role in the whole process of learning from examples. They are mainly initiated by the group leader.
5. Actions led by the cooperative arguments can be divided into five categories, that is, searching for information, exchanging answers, exchanging procedures and principles of problem solving, thinking, associating learned knowledge.
6. The first two kinds of arguments didn't produced new ideas. The third and fourth kinds account for 70% of all, and together with the last kind, these three kinds of cooperative arguments encourage the students to deep process examples. As a result, new ideas and integrated understanding are achieved.
7. It is a common phenomenon that some members cannot answer the questions raised in the discussion. This phenomenon encourages students to deep process examples. At the same time knowledge flaws can be discovered and made up shortly.
8. The personality of members influence their initiative of taking part in the discussion, group leaders should balance the participation of members on purpose..
1、从总体上来看，合作学习班和传统授课班的学生在近迁移和远迁移问题上的成绩都存在显著差异。合作学习的方式优于传统方式。
2、在近迁移问题上，合作学习班和传统授课班的好生之间不存在显著差异，中等生之间也不存在显著差异；而差生之间差异显著，合作学习样例的方式更有效。
3、在远迁移问题上，合作学习班和传统授课班的中等生之间不存在显著差异，差生之间也不存在显著差异；而好生之间差异显著，合作学习样例的方式更有效。
4、引发学生产生应答行为的话语(即合作性话语)贯穿了合作学习样例的整个过程，而且绝大多数由合作小组的组长产生。
5、合作性话语引发的行为可以大致分为五类，即寻找信息，交流答案、交流解题过程及原理、思考、联系旧知识。其中能引发第三、第四类行为的话语占了总数的70％。
6、前两类合作性话语引发的行为没有生成新的观念；后三类合作性话语促使学生对样例进行深入加工，从而生成新的意义和观念并形成完善的理解，这三类话语是导致合作学习方式优于个体单独学习的根本原因所在。
7、小组成员回答不出讨论中的提问是合作学习中常见的一种现象，这能促使成员对样例进行深加工，并有助于及早发现和弥补知识缺陷。
8、成员的个性特征影响了他们参与合作讨论的主动性，长期磨合使组长有意识地均衡成员的参与。
In this study, the effects of two learning-from-example styles , cooperative learning and traditional learning, on problem solving were examined. In order to discover the process and mechanism of learning-from-example in a cooperative way the conversations videotaped in cooperative learning were also analyzed . The results have shown:
1. As a whole, cooperative and traditional learning styles lead to significant performance difference on both near-transfer and far-transfer problems. Cooperative learning style produces better performance than the traditional one does.
2. On near-transfer problems, there is no significant performance difference in the groups of above-average and average students respectfully in experiment and control conditions. However, for below-average students cooperative learning-from-example is more effective.
3. On far-transfer problems, there is no significant performance difference in the groups of average and below-average students respectfully in experiment and control conditions. However, for above-average students cooperative learning-from-example is more effective.
4. Cooperative arguments which lead to responses from members play a critic role in the whole process of learning from examples. They are mainly initiated by the group leader.
5. Actions led by the cooperative arguments can be divided into five categories, that is, searching for information, exchanging answers, exchanging procedures and principles of problem solving, thinking, associating learned knowledge.
6. The first two kinds of arguments didn't produced new ideas. The third and fourth kinds account for 70% of all, and together with the last kind, these three kinds of cooperative arguments encourage the students to deep process examples. As a result, new ideas and integrated understanding are achieved.
7. It is a common phenomenon that some members cannot answer the questions raised in the discussion. This phenomenon encourages students to deep process examples. At the same time knowledge flaws can be discovered and made up shortly.
8. The personality of members influence their initiative of taking part in the discussion, group leaders should balance the participation of members on purpose..
引文
1．陈向明，质的研究方法与社会科学研究，教育科学出版社，2000年。
2．程晓樵，教师在课堂互动中的策略，教育评论，2001年第4期，4-7。
3．大卫．W．约翰逊、罗格．T．约翰逊、卡尔．A．斯密斯著，刘春红、孙海法编译，合作性学习的原理与技巧——在较与学中组建有效的团队，机械工业出版社，2001年8月。
4．高艳，合作学习的分类、研究与课堂应用初探，教育研究，2001年第2期，14—17。
5．高艳、陈丽、尤天贞，关于合作学习的元分析，山东教育科研，2001年第10期，19—21。
6．郭德俊、李原，合作学习的理论与方法，高等师范教育研究，1994年第3期，43—47。
7．李亦菲，示例学习与“条件建构—优化理论”(上)，学科教育，1999年第11期。
8．李亦菲，示例学习与“条件建构—优化理论”(下)，学科教育，1999年第12期。
9．莫雷、刘丽虹，样例表面内容对问题解决类比迁移过程的影响，心理学报，1999，31(3)，313—321。
10．莫雷、唐雪峰，表面概貌对原理运用的影响的实验研究，心理学报．2000，32(4)，399—408。
11．莫雷、唐雪峰，表面概貌对原理运用的影响的实验研究，心理学报，2000，32(4)，399-408。
12．裴利芳，关于示例学习的研究动态，心理科学，1997，20，476—477。
13．裴利芳、朱新明、林仲贤，领域知识与自我解释策略间关系的实验研究，心理学报，1997，29(4)，386—391。
14．唐雪峰、莫雷，表面内容不同方面相似性对样例迁移的影响，心理科学，2003，26(4)，631—633。
15．田学红、李亦菲，基于示例学习的认知技能获得的研究，心理科学，1999，22(6)，529-535。
16．王甦、汪安圣，认知心理学，北京大学出版社，1992年4月。
17．王坦，合作学习的理念与实施，中国人事出版社，2002年。
18．王坦，合作学习述评，山东教育科研，1997年第2期，33—36。
19．王坦，合作学习——原理与策略，学苑出版社，2001年。
20．王坦，论合作学习的基本理念，教育研究，2002年第2期，68—72。
21．王永春，小学数学教学中小组合作学习存在的问题及其解决策略，课程、教材、教法，2002年第8期，34—37。
22．吴庆麟，认知教学心理学，上海科学技术出版社，2000年8月。
23．吴庆麟、胡谊，教育心理学——献给教师的书，华东师范大学出版社，2003年12月。
24．刑强、莫雷，样例的子目标编码对新问题解决中原理通达的作用，应用心理学，2002，8(4)，13—18。
25．刑强、莫雷，样例的子目标编码对新问题解决中原理运用的作用研究，心理发展与教育，2002年第4期，55—59。
26．刑强、莫雷、朱新明，样例学习研究的发展及问题，心理科学进展，2003，11(2)，165—171。
27．许晓川、卢红，从传统学习到合作学习，教育理论与实践，2002，22(11)，16—19。
28．许勇勤、朱新明，关于样例学习中样例设计的若干研究，心理学动态，2000，8(2)，45—50。
29．许远理、朱新明、李亦菲，材料的呈现方式如何影响学习的效果和过程，心理科学，1998年第21卷，560—561。
30．曾琦，合作学习研究的反思与展望，教育理论与实践，2002，22(3)，45—47。
31．张斌，论合作学习及其对学生行为和态度的影响，教育理论与实践，1999，19(9)，41—44。
32．张春莉，数学课中小组合作学习的若干问题研究，教育理论与实践．2002．22(1)，51—55。
33．张春莉，样例和练习在促进接题迁移能力中的作用，心理学报，2001，33(2)，170—175。
34．朱新明、李亦菲，示例演练教学法，辽宁人民出版社，1998年6月。
35. Aleven, V., Stahl, E., Schworm, S., Fischer, F., & Wallace R. (2003). Help seeking and help design in interactive learning environments. Review of Educational Research, 73, 277-320.
36. Anderson, J. R., Fincham, J. M., & Douglass, S. (1997). The role of examples and rules in the acquisition of a cognitive skill. Journal of Experimental Psychology: Learning, Memory, and Cognition, 23, 932-945.
37. Atkinson, R. K., Derry, S. J., Renkl, A., & Wortham, D. (2000). Learning from examples: Instructional principles from the worked examples research. Review of Educational Research, 70(2): 181-214.
38. Bruner, J. S. (1966). Toward a theory of instruction. New York: W. W. Norton.
39. Catrambone, R. (1994a). The effects of labels in example on problem solving transfer. In A. Ram, & K. Eiselt (Eds.), Proceedings of the Sixteenth Annual Conference of the Cognitive Science Society (pp. 159-164). Hillsdale, NJ: Erlbaum.
40. Catrambone, R. (1994b). Improving examples to improve transfer to novel problems. Memory & Cognition, 22, 606-615.
41. Catrambone, R. (1995). Aiding subgoal learning: Effects on transfer. Journal of Educational Psychology, 87, 5-17.
42. Catrambone, R. (1996). Generalizing solution procedures learned from examples. Journal of Experimental Psychology: learning, Memory, and Cognition, 22, 1020-1031.
43. Catrambone, R., & Holyoak, K. J. (1990). Learning and subgoals and methods for solving probability problems. Memory & Cognition, 18, 593-603.
44. Chase, W. G., & Simon, H. A. (1973). The mind's eye in chess. In. W. G. Chase (Ed.),Visual information processing. New York: Academic Press.
45. Chi, M. T., Bassok, M. Levis, M. W., Reimann, P., & Glaser, R. (1989). Self-explanations: How students study and use examples in learning to solve problems. Cognitive Science, 13, 145-182.
46. Chi, M. T., de Leeuw, N., Chiu, M. H., & La Vancher. (1994). Elieiting self-explanations improves understanding. Cognitive Science, 18, 439-477.
47. Glaser, R. (1976). Components of a psychology of instruction: Toward a science of design. Review of Educational Psychology, 46, 1-24.
48. Greeno, J. G., Collins, A. M., & Resnick, L. B. (1996). Cognition and Learning. Handbook of Educational Psychology.
49. John, A. Ross and J. Bradley Cousins (1994), Intentions to seek and give help, and behavior in cooperative learning groups, Contemporary Educational Psychology, 19, 476-484.
50. Jwung, H., Chandler, P., & Sweller, J. (1997). The role of visual indicators in dual sensory mode instruction. Educational Psychology, 17, 329-433.
51. Mousavi, S. Y., Low, R., & Sweller, J. (1995). Reducing cognitive load by mixing auditory and visual presentation modes. Journal of Educational Psychology. 87, 319-334.
52. Paas, F., & Van Merrienboer, J. (1994). Variability of worked examples and transfer of geometrical problem-solving skills: A cognitive-load approach. Journal
of Educational Psychology, 86, 122-133.
53. Parlincsar, A. S. (1998). Social constructivist perspectives on teaching and learning. Annual Review of Psychology. Annual Review of Psychology, 49:345-375.
54. Quilici, j. L., & Mayer, R. E. (1996). Role of examples in how students learn to categorize statistics word problems. Journal of Educational Psychology; 88, 144-161.
55. Reed, S. K., & Bolstad, C. A. (1991). Use of exarnples and procedures in problem solving. Journal of Experimental Psychology: Learning, Memory, and Cognition, 17, 753-766.
56. Renkl, A. (1995). Learning for later teaching: An exploration of mediational links between teaching expectancy and learning results. Learning and Instruction, 5, 21-36.
57. Renkl, A. (1997) Learning from worked-out examples: A study on individual differences. Cognitive Science, 21, 1-29.
58. Renkl, A., Atkinson, R. K., & Maier, U. H. (2000). From example study to problem solving: Smooth transitions help learning.
59. Renkl, A., Stark, R., Gruber, H., & Mandl, H. (1998). Learning from worked-out examples: The effects of example variability and elicited self-explanations. Contemporary Educational Psychology, 23, 90-108.
60. Robert E. Slavin. (1996). Research on cooperative learning and achievement: What we know, what we need to know, Contemporary Educational Psychology, 21, 43-69.
61. Ross, B. H. Distinguishing types of superficial similarities: Different effects on access and use of earlier problems. Journal of Experimental Psychology: Learning, Memory, and Cognition, 1989, 15(2), 456-468.
62. Ross, B. H. This is like that: The use of earlier problems and the separation of similarity effects. Journal of Experimental Psychology: Learning, Memory, and Cognition, 1987, 13(3), 629-639.
63. Sweller, J., & Cooper, G. (1985). The use of worked examples as a substitute for problem solving in learning algebra. Cognition and Instruction, 2, 59-89.
64. Tarmizi, R. A., & Sweller, J. (1988). Guidance during mathematical problem solving. Journal of Educational Psychology, 80,424-436.
65. Trafton, J. G., & Reiser, B. J. (1993). The contributions of studying examples and solving problems to skill acquisition. In M. Poison (Ed.), Proceedings of the
Fifteenth Annual Conference of the Cognitive Science Society (pp. 1017-1022). Hillsdale, NJ: Erlbaum.
66. Van Engen, H. V. (1959). Twentieth century mathematics for the elementary school. The Arithmetic Teacher, 6, 71-76.
67. VanLehn, K. (1996). Cognitive skill acquisition, Annual Review of Psychology, 47, 513-539.
68. Ward, M., & Sweller, J. (1990). Structuring effective worked examples. Cognition and Instruction, 7, 1-39.
69. Zhu, X., & Simon, H. A. (1987). Learning mathematics from examples and by doing. Cognition and Instruction, 4(3): 137-166.
2．程晓樵，教师在课堂互动中的策略，教育评论，2001年第4期，4-7。
3．大卫．W．约翰逊、罗格．T．约翰逊、卡尔．A．斯密斯著，刘春红、孙海法编译，合作性学习的原理与技巧——在较与学中组建有效的团队，机械工业出版社，2001年8月。
4．高艳，合作学习的分类、研究与课堂应用初探，教育研究，2001年第2期，14—17。
5．高艳、陈丽、尤天贞，关于合作学习的元分析，山东教育科研，2001年第10期，19—21。
6．郭德俊、李原，合作学习的理论与方法，高等师范教育研究，1994年第3期，43—47。
7．李亦菲，示例学习与“条件建构—优化理论”(上)，学科教育，1999年第11期。
8．李亦菲，示例学习与“条件建构—优化理论”(下)，学科教育，1999年第12期。
9．莫雷、刘丽虹，样例表面内容对问题解决类比迁移过程的影响，心理学报，1999，31(3)，313—321。
10．莫雷、唐雪峰，表面概貌对原理运用的影响的实验研究，心理学报．2000，32(4)，399—408。
11．莫雷、唐雪峰，表面概貌对原理运用的影响的实验研究，心理学报，2000，32(4)，399-408。
12．裴利芳，关于示例学习的研究动态，心理科学，1997，20，476—477。
13．裴利芳、朱新明、林仲贤，领域知识与自我解释策略间关系的实验研究，心理学报，1997，29(4)，386—391。
14．唐雪峰、莫雷，表面内容不同方面相似性对样例迁移的影响，心理科学，2003，26(4)，631—633。
15．田学红、李亦菲，基于示例学习的认知技能获得的研究，心理科学，1999，22(6)，529-535。
16．王甦、汪安圣，认知心理学，北京大学出版社，1992年4月。
17．王坦，合作学习的理念与实施，中国人事出版社，2002年。
18．王坦，合作学习述评，山东教育科研，1997年第2期，33—36。
19．王坦，合作学习——原理与策略，学苑出版社，2001年。
20．王坦，论合作学习的基本理念，教育研究，2002年第2期，68—72。
21．王永春，小学数学教学中小组合作学习存在的问题及其解决策略，课程、教材、教法，2002年第8期，34—37。
22．吴庆麟，认知教学心理学，上海科学技术出版社，2000年8月。
23．吴庆麟、胡谊，教育心理学——献给教师的书，华东师范大学出版社，2003年12月。
24．刑强、莫雷，样例的子目标编码对新问题解决中原理通达的作用，应用心理学，2002，8(4)，13—18。
25．刑强、莫雷，样例的子目标编码对新问题解决中原理运用的作用研究，心理发展与教育，2002年第4期，55—59。
26．刑强、莫雷、朱新明，样例学习研究的发展及问题，心理科学进展，2003，11(2)，165—171。
27．许晓川、卢红，从传统学习到合作学习，教育理论与实践，2002，22(11)，16—19。
28．许勇勤、朱新明，关于样例学习中样例设计的若干研究，心理学动态，2000，8(2)，45—50。
29．许远理、朱新明、李亦菲，材料的呈现方式如何影响学习的效果和过程，心理科学，1998年第21卷，560—561。
30．曾琦，合作学习研究的反思与展望，教育理论与实践，2002，22(3)，45—47。
31．张斌，论合作学习及其对学生行为和态度的影响，教育理论与实践，1999，19(9)，41—44。
32．张春莉，数学课中小组合作学习的若干问题研究，教育理论与实践．2002．22(1)，51—55。
33．张春莉，样例和练习在促进接题迁移能力中的作用，心理学报，2001，33(2)，170—175。
34．朱新明、李亦菲，示例演练教学法，辽宁人民出版社，1998年6月。
35. Aleven, V., Stahl, E., Schworm, S., Fischer, F., & Wallace R. (2003). Help seeking and help design in interactive learning environments. Review of Educational Research, 73, 277-320.
36. Anderson, J. R., Fincham, J. M., & Douglass, S. (1997). The role of examples and rules in the acquisition of a cognitive skill. Journal of Experimental Psychology: Learning, Memory, and Cognition, 23, 932-945.
37. Atkinson, R. K., Derry, S. J., Renkl, A., & Wortham, D. (2000). Learning from examples: Instructional principles from the worked examples research. Review of Educational Research, 70(2): 181-214.
38. Bruner, J. S. (1966). Toward a theory of instruction. New York: W. W. Norton.
39. Catrambone, R. (1994a). The effects of labels in example on problem solving transfer. In A. Ram, & K. Eiselt (Eds.), Proceedings of the Sixteenth Annual Conference of the Cognitive Science Society (pp. 159-164). Hillsdale, NJ: Erlbaum.
40. Catrambone, R. (1994b). Improving examples to improve transfer to novel problems. Memory & Cognition, 22, 606-615.
41. Catrambone, R. (1995). Aiding subgoal learning: Effects on transfer. Journal of Educational Psychology, 87, 5-17.
42. Catrambone, R. (1996). Generalizing solution procedures learned from examples. Journal of Experimental Psychology: learning, Memory, and Cognition, 22, 1020-1031.
43. Catrambone, R., & Holyoak, K. J. (1990). Learning and subgoals and methods for solving probability problems. Memory & Cognition, 18, 593-603.
44. Chase, W. G., & Simon, H. A. (1973). The mind's eye in chess. In. W. G. Chase (Ed.),Visual information processing. New York: Academic Press.
45. Chi, M. T., Bassok, M. Levis, M. W., Reimann, P., & Glaser, R. (1989). Self-explanations: How students study and use examples in learning to solve problems. Cognitive Science, 13, 145-182.
46. Chi, M. T., de Leeuw, N., Chiu, M. H., & La Vancher. (1994). Elieiting self-explanations improves understanding. Cognitive Science, 18, 439-477.
47. Glaser, R. (1976). Components of a psychology of instruction: Toward a science of design. Review of Educational Psychology, 46, 1-24.
48. Greeno, J. G., Collins, A. M., & Resnick, L. B. (1996). Cognition and Learning. Handbook of Educational Psychology.
49. John, A. Ross and J. Bradley Cousins (1994), Intentions to seek and give help, and behavior in cooperative learning groups, Contemporary Educational Psychology, 19, 476-484.
50. Jwung, H., Chandler, P., & Sweller, J. (1997). The role of visual indicators in dual sensory mode instruction. Educational Psychology, 17, 329-433.
51. Mousavi, S. Y., Low, R., & Sweller, J. (1995). Reducing cognitive load by mixing auditory and visual presentation modes. Journal of Educational Psychology. 87, 319-334.
52. Paas, F., & Van Merrienboer, J. (1994). Variability of worked examples and transfer of geometrical problem-solving skills: A cognitive-load approach. Journal
of Educational Psychology, 86, 122-133.
53. Parlincsar, A. S. (1998). Social constructivist perspectives on teaching and learning. Annual Review of Psychology. Annual Review of Psychology, 49:345-375.
54. Quilici, j. L., & Mayer, R. E. (1996). Role of examples in how students learn to categorize statistics word problems. Journal of Educational Psychology; 88, 144-161.
55. Reed, S. K., & Bolstad, C. A. (1991). Use of exarnples and procedures in problem solving. Journal of Experimental Psychology: Learning, Memory, and Cognition, 17, 753-766.
56. Renkl, A. (1995). Learning for later teaching: An exploration of mediational links between teaching expectancy and learning results. Learning and Instruction, 5, 21-36.
57. Renkl, A. (1997) Learning from worked-out examples: A study on individual differences. Cognitive Science, 21, 1-29.
58. Renkl, A., Atkinson, R. K., & Maier, U. H. (2000). From example study to problem solving: Smooth transitions help learning.
59. Renkl, A., Stark, R., Gruber, H., & Mandl, H. (1998). Learning from worked-out examples: The effects of example variability and elicited self-explanations. Contemporary Educational Psychology, 23, 90-108.
60. Robert E. Slavin. (1996). Research on cooperative learning and achievement: What we know, what we need to know, Contemporary Educational Psychology, 21, 43-69.
61. Ross, B. H. Distinguishing types of superficial similarities: Different effects on access and use of earlier problems. Journal of Experimental Psychology: Learning, Memory, and Cognition, 1989, 15(2), 456-468.
62. Ross, B. H. This is like that: The use of earlier problems and the separation of similarity effects. Journal of Experimental Psychology: Learning, Memory, and Cognition, 1987, 13(3), 629-639.
63. Sweller, J., & Cooper, G. (1985). The use of worked examples as a substitute for problem solving in learning algebra. Cognition and Instruction, 2, 59-89.
64. Tarmizi, R. A., & Sweller, J. (1988). Guidance during mathematical problem solving. Journal of Educational Psychology, 80,424-436.
65. Trafton, J. G., & Reiser, B. J. (1993). The contributions of studying examples and solving problems to skill acquisition. In M. Poison (Ed.), Proceedings of the
Fifteenth Annual Conference of the Cognitive Science Society (pp. 1017-1022). Hillsdale, NJ: Erlbaum.
66. Van Engen, H. V. (1959). Twentieth century mathematics for the elementary school. The Arithmetic Teacher, 6, 71-76.
67. VanLehn, K. (1996). Cognitive skill acquisition, Annual Review of Psychology, 47, 513-539.
68. Ward, M., & Sweller, J. (1990). Structuring effective worked examples. Cognition and Instruction, 7, 1-39.
69. Zhu, X., & Simon, H. A. (1987). Learning mathematics from examples and by doing. Cognition and Instruction, 4(3): 137-166.