Chapter 50

THE LESSON UNIT

=What Constitutes a Lesson Problem.=--The foregoing analysis and description of the learning process has shown that the ordinary school lesson is designed to lead the pupil to build up, or organize, a new experience, or, as it is sometimes expressed, to gain control of a unit of valuable knowledge, presented as a single problem. From what has been learned concerning the relating activity of mind, however, it is evident that the teacher may face a difficulty when he is called upon to decide what extent of knowledge, or experience, is to be accepted as a knowledge unit. It was noted, for example, that many topics regularly treated in a single lesson fall into quite distinct sub-divisions, each of which represents to a certain extent a separate group of related ideas and, therefore, a single problem. On the other hand, many different lesson experiences, or topics, although taught as separate units, are seen to stand so closely related, that in the end they naturally organize themselves into a larger single unit of knowledge, representing a division, of the subject of study. From this it is evident that situations may arise, as in teaching the classes of sentences in grammar, in which the teacher must ask himself whether it will be possible to take up the whole topic with its important sub-divisions in a single lesson, or whether each sub-division should be treated in a single lesson.

=How to Approach Associated Problems.=--Even when it is realized that the related matter is too large for a single lesson, it must be decided whether it will be better to bring on each sub-division as a separate topic, and later let these sub-divisions synthesise into a new unity; or whether the larger topic should be taken up first in a general way, and the sub-divisions made topics of succeeding lessons. In the study of mood in grammar, for example, shall we introduce each mood separately, and finally have the child synthesise the separate facts; or shall we begin with a lesson on mood in general, and follow this with a study of the separate moods? In like manner, in the study of winds in geography, shall we study in order land and sea breezes, trade-winds, and monsoons, and have the child synthesise these facts at the end of the series; or shall we begin with a study of winds in general, and follow this with a more detailed study of the three classes of winds?

WHOLE TO PARTS

=Advantages.=--The second of these methods, which is often called the method of proceeding from whole to parts, should, whenever possible, be followed. For instance, in a study of such a lesson as _Dickens in the Camp_, the detailed study of the various stanzas should be preceded by an introductory lesson, bringing out the leading thought of the poem, and noting the sub-topics. When, in an introductory lesson, the pupil is able to gain control of a large topic, and see the relation to it of a given number of sub-topics, he is selecting and relating the parts of the whole topic by the normal analytic-synthetic method. Moreover, in the following lessons, he is much more likely to appreciate the relation of the various sub-topics to the central topic, and the inter-relations between these various sub-topics. For this reason, in such subjects as history, literature, geography, etc., pupils are often introduced to these large divisions, or complex lesson units, and given a vague knowledge of the whole topic, the detailed study of the parts being made in subsequent lessons.

=Examples.=--The following outlines will further illustrate how a series of lessons (numbered I, II, III, etc.) may thus proceed from a first study of the larger whole to a more detailed study of a number of subordinate parts.

THE ST. LAWRENCE RIVER SYSTEM

_I. Topic.--The St. Lawrence River:_

Position, size, extent of system, other characteristics. Importance--historical, commercial, industrial.

_II. Sub-topic 1.--Importance historically:_

Open mouth to Europe; Open door to continent; Cartier, Champlain. System of lakes and rivers large and small gave lines of communication, inviting discovery and subsequent development and settlement.

_III. Sub-topic 2.--Importance commercially:_

Large tracts of valuable land, timber, etc., made available. Highway--need of such between East and West. Difficulties to be overcome, canal, ships. Competition of railways, How? Classes of goods back and forth. Avenue to and from the wheat land.

_IV. Sub-topic 3.--Importance industrially:_

Great commercial centres--where located and why? Water powers, elevators, manufacturing of raw materials made available in the large areas; Immigration; Fishing.

STUDY OF BACTERIA

_I. Topic.--Bacteria:_

What they are; relations, comparisons; other plants in same class, or those of higher orders; size, shape; where found; conditions of growth; propagation; modes of distribution; etc.

_II. Sub-topic 1.--Our interest in bacteria, arising out of the injury or good they do:_

(_a_) Injury: Decay of fruits, trees, tissues, etc., diseases--diphtheria, typhoid, tuberculosis; how developed, conditions, favourable toxins.

(_b_) Benefits: In soil, cheese, butter, etc.; chemical action, building new compounds and breaking up other compounds.

_III. Sub-topic 2.--Our interest in controlling them; the methods based on mode and conditions of growth, etc.:_

(_a_) Prevention: Eliminating favourable conditions; low temperature, high temperatures, cleanliness; sewerage disposal; clean cow-stables, cellars, kitchens, etc.; antiseptics--carbolic, formalin, sugar for fruit, sealing up; quarantine, vaccination, antitoxin.

(_b_) Cultures,--alfalfa, cheese, butter, under control.

GEOGRAPHY OF EUROPE

_I. Topic.--Europe:_

What interest to us; why we study it; position, latitude, near water, boundaries, size; Surface features--highlands, lowlands, drainage rivers, coast-line, etc. Climate--temperature (means, Jan., July), wind, moisture.

_II. Sub-topic 1.--Products (based on above conditions):_

Vegetation, animal, mineral; vary over area according to physical climatic, and geological conditions; Kinds of products of each class, in each area, etc.

_III. Sub-topic 2.--Occupations (based on Lesson II):_

Study of operations and conditions favourable and unfavourable under which each product is produced, gathered, and manufactured. Industries, arising from work on the raw materials.

_IV. Sub-topic 3.--Trade and Commerce (based on Lessons II and III):_

Transportation, producers selling and manufacturers buying raw material, distributed to homes in country and city, to factories within the region itself, to regions beyond, across oceans, etc. Manufactured products sent out, exports and imports.

_V. Sub-topic 4.--Civil advantages (based on Lessons I, III, and IV):_

Conditions of living--homes, dress, work and pleasure; trades, education, government, social, religious, etc.

PARTS TO WHOLE

The method of whole to parts cannot be followed in all cases even where a number of lesson units may possess important points of inter-relation. Although, for instance, simple and compound addition and addition of fractions are only different phases of one process, no one would advocate the combining of these into such a unified lesson series. In Canadian History, also, although the conditions of the Quebec Act, the coming of the United Empire Loyalists, and the passing of the Constitutional Act, have definite points of inter-relation, it would nevertheless be unwise to attempt to evolve these out of a single complex lesson unit. In such cases, therefore, the synthesis of the various parts must be made as the lessons proceed. Moreover, it is well to ensure the complete organization of the elements by means of an outline review at the end of the lesson series. The student-teacher will meet an example of this process under the topical lesson in Chapter XVII.

PRECAUTIONS

It is evident from the above considerations, that certain precautions should be observed in deciding upon the particular subject-matter to be included in each lesson topic.

1. A just balance should be maintained between the difficulty of each lesson unit and the ability of the class. Matter that is too easy requires no effort in its mastery and hence is uninteresting. Matter that is too difficult discourages effort, and is, therefore, equally uninteresting. It should be sufficiently easy for every pupil to master, and sufficiently difficult to require real effort.

2. The amount of matter included should be carefully adjusted to the length of time taken for the lesson and to the attainments of the class. If too much is attempted, there will be insufficient time for adequate drill and review, and hence there will be lack of thoroughness. If too little is attempted, time will be wasted in needless repetition.

3. Each unit of instruction in any subject should, in general, grow out of the preceding unit taken in that subject, and be closely connected with it. It is in this way that a pupil's interest is aroused for the new problem and his knowledge becomes organized. Neglect in this regard results in the possession of disconnected and unsystematized facts.

Each lesson should contain one or more central facts around which the other facts are grouped. This permits easy organization of the material of the lesson, and ensures its retention by the pupils. Further, the pupils are by this means trained to discriminate between the essential and the non-essential.