Science Activities-Projects and Curriculum Ideas in STEM Classrooms最新文献

The Earth's oceans are home to a diverse array of life, from large marine mammals to microscopic organisms. Among the most important are the marine phytoplankton, which comprise the basis of marine food webs, and also produce a large percentage of the Earth's oxygen through photosynthesis. Although the vast majority of phytoplankton are essential to ocean health, several dozen species produce potent toxins, and can form what are called Harmful Algal Blooms (HABs). This activity focuses on the importance of HABs, as well as the types of data scientists collect to understand blooms. In the classroom exercises, students will calculate the proportional abundance (% contribution) of five HAB species present in water samples, and use these data to create pie graphs to depict species composition. Students will then compare these results with levels of HAB toxins in water samples collected over the same time period. Thought questions challenge students to develop hypotheses regarding how changes in the HAB community may relate to observed trends in toxin concentrations. This activity was successfully taught to visually impaired students who were able to complete the pie charts and answer the thought questions.

Marine phytoplankton comprise the foundation of oceanic food webs and generate most of the Earth's oxygen. Of the many phytoplankton species in the ocean, a few dozen produce potent toxins, and at high concentrations can form what are called Harmful Algal Blooms (HABs) or "red tides" that can discolor marine waters. Managers and scientists have been monitoring coastal waters and shellfish resources for HABs and their toxins to ensure seafood safety and understand why blooms occur. This educational activity focuses on a prominent HAB species that causes paralytic shellfish poisoning (PSP). Students will learn about the importance of HABs and PSP, as well as how scientists collect and use data to understand and predict blooms. Students will plot data on HAB species collected by scientists over multiple years of sampling. Students will also plot results over time and across regions, report on observed patterns, and complete grade-appropriate calculations. Lastly, group discussion will focus on determining whether geographic patterns exist that might influence where shellfish beds are closed. This activity is timely given the widespread wildlife mortalities and beach closures due to Florida red tide, as well as recent dog deaths attributed to exposure to freshwater cyanobacteria (blue-green algae) blooms.

Teachers can use pedometers to facilitate inquiry learning and show students the need for mathematics in scientific investigation. The authors conducted activities with secondary students that investigated intake and expenditure components of the energy balance algorithm, which led to inquiries about pedometers and related data. By investigating the accuracy of pedometers and variables that may impact reported step counts, students can better understand experimental design and statistical concepts. Students can also examine other data (distance walked, kilocalories expended) using multifunction pedometers and apply the concepts of correlation and regression. This topic fits well with thematic learning and responds to concerns about excess energy intake and insufficient physical activity in the U.S. population.