I. Curricular Framework

Concept:

Classification

Essential Question:

Why is there a need to classify living things?

Bridge:

Images of Living Things

Content:

Outcomes:

II. Standards Aligned

III. Instruction and Assessment

1. Connect: Connecting to the Concept Experientially

Objective: To have students actively realize that many things in their everyday experience are classified or organized so that they may be used/found more readily and then to create a class experience in which the students devise a scheme to classify a common object.

Activity: The students begin this concept by surfacing as many things in their everyday experiences as they can which are classified or organized. They are usually very good at contributing items such as: dictionaries, supermarkets, libraries, department stores, class schedules, etc. Then they are asked to make a large circle around the periphery of the room; remove their left shoe and push it into the center of the circle. (At this point, they're not sure what is going to happen.) The teacher asks for three volunteers, one to go to the board and two to separate the shoes. The task is to devise a scheme, based on similarity of structure, by which the shoes can be broken down into smaller and smaller piles until each student receives her/his own shoe.

Assessment: Participation of the students in contributing examples of everyday things which are classified and their cooperation in joining in the show activity.

2. Attend: Attending to the Connection

Activity: The scheme that appears on the board almost always looks something like the example below:


LEFT SHOES

LACES NO LACES

NOT PENNY LOAFERS PENNY LOAFERS

Students freely contribute suggestions for identifying the categories and become more attentive to subtle distinguishing features.

Assessment: Quality and degree of student involvement.

Assessment, Phase One, Level of Engagement, Fascination:

3. Image: Creating a Mental Picture

Objective: The students will begin to make the bridge between the classification of ordinary objects and the task of classifying millions of living things.

Activity: For homework, the students are asked to find pictures of living things. Any living thing is acceptable, so some even bring in photographs of their family members or pets. They bring these pictures to class the next day and the teacher goes around looking at what they've brought, making comments, etc. Before the next class period, these contributions will be hung around the classroom as a visual reminder of the variety of living things. (And this is only a small sampling.) After the presentation of Aristotle and Linnaeus' Schemes, the teacher comes back to this Quadrant 2, Right Mode and puts out on a desk representative members of the different kingdoms. For example, photographs of magnified bacteria, a sample of pond water, a few mushrooms from the supermarket, the classroom pet hamsters and a handy plant, moldy bread, a goldfish, a flower, etc. can be gathered. Then the students are again asked to group these living things based on similarities of features.

Assessment: Quality of student responses: their willingness to bring in pictures and critically identify distinguishing structures/features in living things.

Assessment, Phase Two, Seeing the Big Picture:

4. Inform: Receiving Facts & Knowledge

Objective: To provide the students with the historical basis of biological classification, giving Aristotle's simple scheme, Linnaeus' contributions of levels of organization and binomial nomenclature and Whittaker's presently recognized five kingdom scheme.

Activity: Using the blackboard, colored chalk and imitating the same type of scheming patterns that the students used for the shoe activity, the teacher shows the progression and increasing complexity of how scientists have attempted to put living things in some kind of order so that they can be studied. When doing binomial nomenclature, many examples are given with a little explanation of why Latin was chosen. When explaining the Levels of Organization (Kingdom, Phylum, Class, Order, Family, Genus, Species) an analogy is drawn using the location of the teacher, i.e., Kingdom = country, Phylum = state, Class = city, Order = street, Family = #, Genus = last name, Species = first name. The most important point is that the more of these levels two organisms share in common, the more closely related they are. Finally, Whittaker's Five Kingdom Scheme is presented.

Assessment: Quality of students' notes; their ability to correctly answer class questions involving analysis of relationship charts and identification of the key characteristics and example organisms of each of the Kingdoms.

Assessment, Phase Three, Success with Acquiring Knowledge:

5. Practice: Developing Skills

Objective: To confirm the students' ability to identify degree of relationships among living things and to check that they can properly place organisms in the kingdom to which they belong based on their characteristics.

Activity: For this octant, students 1) complete a worksheet where they fill-in appropriate levels of organization to establish closeness of relationships among four different organisms, and 2) work on a small group activity which involves them placing a number of different organisms in the appropriate kingdoms based on structural features and characteristics.

Assessment: Quality of students' involvement in the activities: their success in completing the chart; their active participation in completing the activity.

Assessment, Phase Four, Success with Acquiring Skills:

6. Extend: Extending Learning to the Outside World

Objective: To have the students learn how to use an already prepared tool for identification of living things, a classification key.

Activity: Working in pairs, the students discover how to use a prepared classification key. Most lab books contain at least one exercise where the students are taught to use a key to identify a series of unknown organisms. Some books provide pictures of families of fish, or sharks, or dinosaurs, or even imaginary monsters.

Assessment: Success of the students in correctly identifying the unknown organisms by using the key provided.

7. Refine: Refining the Extension

Objective: To have the students confirm their understanding of classification keys by constructing their own keys for leaves or fish or some other small sampling of living things.

Activity: Now that they have used and studied keys, the students are given a set of pictures of fish or leaves, something different than what they have already used and asked to construct their own dichotomous key. They then swap the key with a partner to ensure that it is true to the form and that it works.

Assessment: Students' ability to successfully construct and use a dichotomous classification key.

8. Perform: Creative Manifestation of Material Learned

Objective: To have the students re-own the material by taking some objects of interest to them and organizing/classifying them by similarity of structure and then devising a key so that others may identify them.

Activity: The students are asked to take something of their own choosing (cars, tapes, silver patterns, sports balls, cereals) and make a key for their identification. Usually this is given as a homework assignment. They usually draw or cut out pictures of the items with which they are working. Then they construct a key so that someone not knowing the items can correctly identify the items. In class the next day, students exchange keys and test them for accuracy.

Assessment: Quality of students choice of items, numbers of objects used and accuracy of the key in terms of form and purpose.

Assessment, Phase Five,Performance, Creative Use of Material Learned: