Third-grade students will be able to identify a variety of common animals living in or around a pond. The students will likely name frogs, fish, tadpoles, turtles and ducks. However, at this level the students should also be capable of classifying the animals found in a pond ecosystem. The children can divide the animals into groups by physical characteristics, methods of birth (such as laying eggs) and eating habits. Discussion of how the animals' characteristics help them survive and if any adaption has taken place is necessary at this time. Topics such as coloring (camouflage) are important.
In addition to animal life, it is critical for third-grade students to also realize that plant life plays an important part in the pond ecosystem. Lily pads and cattails are common forms of plant life that children can describe. Third-grade students will be able to recognize other plants that contribute to the pond, such as algae. They will learn how the plant life contributes to the environment.
After recognizing the components of a pond ecosystem, the third-grade students will learn how the environment's parts work together as one. During this discussion, students will arrive at concepts such as the importance of the oxygen released into the water and air by the algae and other plant life (producers). They will gain information about how snails and other decomposers break down the waste and decay to allow for a sufficient oxygen supply. Other terms, such as consumer, predator, prey, carnivore, herbivore and omnivore, will also be introduced. Students will identify the animals or plants that fit into these categories.
Students at this level also need information pertaining to factors that upset the pond ecosystem. These factors include pollution by people as well as natural and animal pollutants. Fertilizers, chemicals and oil all have a negative impact on the pond life. Climate, abundance or lack of rain, and erosion can all also affect the pond ecosystem. An interruption of the food chain, such as the killing or removal of a species, also impacts the environment at the pond.