Due to a last-minute scheduling change, we had the opportunity to spend our final lab in the computer lab today instead of tomorrow. This worked out nicely, as many groups realized yesterday their tri-fold presentation boards needed additional content. After today, students will need to arrange computer time outside of class if additional research is needed to complete the project. We will be back in the classroom tomorrow assembling tri-fold presentation materials and discussing anticipated audience questions.
For our final day with the Chromebooks, students were asked to research how algae fit into the Puget Sound food web. After a student mentioned that algae obtain energy through photosynthesis, students were introduced to the formal scientific concept of limiting factors. We used the example of phosphate, a chemical students measured while on the field trip which is also a critical component of ATP. Photosynthesis is the process of storing the energy from sunlight within a molecule of glucose, and that energy is transferred to ATP during the process of cellular respiration. ATP, or adenosine triphosphate, consists of an adenine group with three phosphate molecules attached. When there is an excess of phosphate in the environment, the organisms that live there are not limited in their ability to multiply. Therefore, phosphate availability is a limiting factor for algal blooms. Michigan State University has a more in-depth scientific explanation of limiting factors in aquatic environments.
As student projects take shape, students were reminded that they need to dig deeply into the science to explore why their proposed solution will reduce the frequency of harmful algae blooms. Next week, they will have some additional computer time coupled with time to work on their posters and presentations. The posters and presentations will be the action piece of the project – students will present their work to their stakeholders and seek feedback about their proposed solutions.
After reaching out to stakeholders yesterday, many student groups were excited to report their stakeholder had replied back! Energized by the connection, students embraced the task of researching and then using their understanding of science to propose a solution to reduce the effect and frequency of harmful algal blooms on the Puget Sound ecosystem. To help guide their research efforts, students were encouraged to review the Know and Need to Know lists they assembled last week when we kicked off the Problem Based Learning task (see October 15th post). Today, students also learned that they will have a few additional days of computer-based research time, and they began thinking about how they will represent their individual projects to their stakeholders on Tuesday, November 3.
On Wednesday, we kicked off the Evolution unit with our first lesson. In Lesson 1, students watched a video about the evolution of soccer and then brainstormed other everyday things that have evolved over time. Student ideas included the evolution of vehicles, animals, society, technology, and medicine. In the lesson, students learned that DNA can change through missense mutations, nonsense mutations, and frameshift mutations. After the lesson, students worked with a partner to investigate a hypothetical scenario requiring the integration of research skills, critical reading skills, recollection of the Central Dogma, and application of DNA mutations. The investigation will conclude on Monday. By the end of class Thursday, most students had successfully answered questions 2-6 of the worksheet. As the events of 1995 and 2000 were before many of the students were born, we watched the following videos to bring closure to that part of the investigation and to introduce students to part of Seattle cultural history.