Outline
(note an outline is not required, but may help you prepare your report)
Carbon dioxide is added to the atmosphere by:
   decay of vegetation, respiration (exhalations of animal life), combustion of fossil fuels, deforestation

Carbon dioxide is removed from the atmosphere by:
    photosynthesis, oceans (hold 50 times more CO₂ than the atmosphere)

Carbon dioxide concentration is increasing:
    has increased about 20% (from 315 ppm to 370 ppm) between 1958, when direct measurements were
    started (Mauna Loa, Hawaii), and the present day.
    Concentration measurements prior to 1958 come from ice cores.  Ice core data show concentration
    was about 280 ppm up until the early 1800s then started to increase.
    concentration might reach 500 ppm by 2100.

Carbon dioxide is a greenhouse gas:
    increasing amounts of CO₂ and other greenhouse gases [methane, nitrous oxide, CFCs, and water
    vapor] may cause a 1.4 to 5.8 C increase in global average surface air temperature.

Report
    Carbon dioxide is added to the atmosphere by respiration (we breathe in oxygen and breath out carbon

dioxide), decay, combustion of fossil fuels, and deforestation.  Living plants remove CO₂ from the air

during photosynthesis and add oxygen to the air (that's why deforestation adds CO₂ to the air).  CO₂

also dissolves in the world's oceans; they contain about 50 times as much CO₂ as the atmosphere.

    There is a lot less CO₂ in the atmosphere than nitrogen or oxygen, but the CO₂ concentration is

increasing.  In 1958, when measurements of atmospheric CO₂ were started at the Mauna Loa

Observatory in Hawaii, the concentration was 315 ppm.  The concentration is now closer to 370 ppm. 

CO₂ is a greenhouse gas (together with methane, nitrous oxide, and chlorofluorocarbons).  There is

concern that increasing concentrations of greenhouse gases could cause global average surface air

temperatures to increase.  It has been possible to determine atmospheric CO₂ concentrations prior to

1958 by analyzing ice cores from Greenland and Antarctica.  The CO₂ concentration was fairly constant

at 280 ppm up until the early 1800s, when it started to increase.  Predictions are that CO₂ concentrations

may increase to 500 ppm which may cause a 1.4 to 5.8 C of warming.  This could have a lot of

undesirable effects on our weather.


Grading
A total of 3.5 content pts and 2.5 writing quality pts were available on this report.  This particular report earned 3 content points and 2 writing quality points for a total of 5 pts.  The grader commented on the 3 items highlighted in red above.  Deforestation adds CO₂ to the atmosphere because dead plants decay,  ppm stands for parts per million and are units of concentration, the report could include a specific example or two of undesirable effects of global warming on the weather.