[Middle School] Art. Excrpt._Demo Lesson Plan Note 1

1. Preparing for the demonstration
2. The demonstration
3. Guided inquiry

Engage students by casually performing the demonstration a few times without comment. Often students will initiate discussion by asking what is in the flask or why the color changes are taking place. At this point ask them to formally state what they have observed as you record their observations on the board or overhead.

You may wish to have students record observations on a worksheet or in a class notebook to help develop writing skills and produce a permanent record of their thoughts. This is done before any mention of scientific inquiry.

Next ask students, “Why does shaking the flask cause the observed color changes?” Students are challenged to give possible answers. As their suggestions are stated, write them on the board or overhead.

4. Common student hypotheses and testing as a class
5. Mics. Excrpt

The blue bottle reaction: For middle school students it is sufficient to describe the chemistry in more general terms.

The flask originally contained air above the liquid and shaking the flask dissolved a small amount of oxygen from the air, which reacted with another chemical in the liquid to produce the blue product. The blue product then was slowly consumed or used up during a second reaction, which resulted in the liquid becoming colorless once again.

6. Conclusion

The abilities to propose experiments, make observations, and use data to justify conclusions are critical to the scientific process.

Investigation of the reaction can be adequately discussed in middle school using general terms such as blue substance and colorless gas.

The demonstration process allows the teacher to maintain control while guiding an inquiry into the chemical system.

This involves students in an investigation early, even on the first day of class if the teacher chooses, before they have any experience in hands-on group activities.*****

The demonstration format also minimizes material needs and safety issues.*****

Teachers help students use evidence to accept, eliminate, or modify hypotheses.

Students build ownership as later in the year they propose and design experiments, make observations, draw conclusions, and propose alternative hypotheses.

- Authorships

William C. Deese (wcdeese@latech.edu) is the
T.W. Ray Johnson professor of chemistry and Linda

Ramsey (lramsey@latech.edu) is director of CATALyST
and an assistant professor of biological sciences
at Louisiana Tech University in Ruston, Louisiana.

Cathi Cox (ccox@lincolnschools.org) is the Project
ACHIEVE coordinator for Lincoln Parish Schools in
Ruston, Louisiana.