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The term population as it applies to ecology will be defined and students will understand what it implies in ecological context.
Population growth is determined by various factors and characteristics of population growth will be discussed both in developing and developed nations.
Students will be required to gain a clear understanding of exponential and logistic growth curves. They will be drawing the curves based on hypothetical data that will be provided to them..
Patterns of human population growth and the future tendency in human population growth will be indicated.

General objectives: Students will be aware of what ecology mean and be able to recognize the interactions that exist among and between biotic and abiotic factors. They will acquire knowledge that will enable them contribute to the conservation and wise use of biodiversity and natural resources as a whole.

Specific objectives
At the end of this chapter students will know what factors affect population growth.

They will understand how to explain population growth curves
They will get information on the tendency of future population growth in their country as well as in the other countries of the world.

Student activity: Drawing growth curves from data that will be available to them and interpret the graphic information in written statements.

Materials and methods

Students will have graph papers, rulers and pencils
Data will be made available and each student is expected to use it
Each student will draw 2 graphs: one for exponential growth and the other for logistic growth curve.
Each graph should be discussed by indicating what happens at each stage of population growth.

Assessment

Their ability of discussing the growth curves is an indicator of their understanding of the subject matter and finally they will be tested on quizzes to be offered at the end of the unit.

Note: On the same day students will be taken to streamside near Woodson High School, to help them observe some real characters tics of ecosystems. Some of the things that they will observe will be an example of climax community, standing and flowing water, main river and tributary and the interdependence of abiotic and biotic factors.

Hypothetical data for Exponential and Logistic growth curves

Year	Population	Year	Population
1992	5000	1992	5000
1993	6000	1993	6000
1994	7500	1994	7500
1995	9000	1995	9000
1996	12000	1996	12000
1997	22000	1997	22000
1998	40000	1998	40000
1999	50000	1999	78000
2000	55000	2000	155000
2001	54800	2001	300000
2002	54804	2002	900000
2003	54802	2003	2000000
2004	54801	2004	5000000

Results:

1. Students were able to draw the graphs for exponential and logistic growtth curves and they were able to interepret what each graph implies in the context of population growth in different regions of the world.
2. Students were able to assess their own work while each group was presenting its search results to the class. It means a group can compare the quality of its graph with the rest of the groups and will identify its strenght and weakness.
3. I informed them that this kind of cooperative learning is a good way of assessing their own work and at the same time it is a quick way of getting ample information within a short period of time.