All posts by David Swart

High school science teacher
Central Dogma, Genetics

Central Dogma: Introduction to DNA

Leave a comment

We began class with a new seating chart.  Students organized themselves by birth month and were seated in pairs.  Students were reminded how important it is to make new friends and engage with new people to learn new ideas and ways of approaching a scientific challenge.

After the seating chart, students were provided with a timeline for making up work from the last two weeks of Unit 4.  All late work and revisions are due by this Friday.  Students were also reminded to check in on the class website daily and to monitor the new Twitter feed for interesting science articles.

Next, we launched in to Unit 5: Central Dogma.  Students were asked to write down everything they know about DNA and then shared their knowledge with their new table partner.  Students were encouraged to use the agree/disagree structured partner talk strategy.  Student pairs then shared one piece of information about DNA that they discussed by writing it on a class white board.  An example of the information from one class is given below.

IMG_6571IMG_6572IMG_6573IMG_6574IMG_6575IMG_6576

Finally, students received a few slides of instruction regarding Central Dogma vocabulary before we watched the first 16 minutes of Cosmos: Episode 2.  The last slide of the lesson lists the questions students answered while watching the video.

Energy, Matter, Organization

Energy, Matter, and Organization: Ocean Acidification – Day 1

Leave a comment

We kicked off the lesson with an entry task focused on why we use fossil fuel combustion (to produce energy).  Students were then asked to consider one unintended consequence of fossil fuel combustion (releasing carbon dioxide into the atmosphere).  We followed that discussion with a video about ocean acidification (below) before concluding the lesson with an experiment in which students re-created the conditions of ocean acidification by measuring the change in pH after exhaling through a straw placed in water for one minute.

 

Energy, Matter, Organization

Energy, Matter, and Organization: Combustion – Day 2

Leave a comment

We continued our study of combustion with a review of why burning candles lose mass.  We watched a video in which Mr. Anderson describes not only the process of combustion but also the concept of Conservation of Mass.  At the end of the video, he mentions how neat a candle burning in the space shuttle looks, so I also included a video of the recent FLEX2 experiment aboard the International Space Station.  After the lesson, students completed a quiz connecting the concepts of combustion, cellular respiration, and photosynthesis.

Energy, Matter, Organization

Energy, Matter, and Organization: Combustion – Day 1

Leave a comment

The lesson for Monday centered on the concept of combustion.  We dove into vocabulary about chemistry and even balanced an equation!  We then created a table comparing photosynthesis, cellular respiration, and combustion.  Because some classes were ready, we also discussed the combustion of paraffin wax in a burning candle.  Yesterday’s lesson can be viewed by clicking here.

Energy, Matter, Organization

Energy, Matter, and Organization: Revising a Scientific Conclusion

Leave a comment

We began class with an entry task asking students to ponder: where do trees get their mass from?  Students had some time to think about the question and write or draw pictures describing their ideas.  Selected students or small groups of students were asked to share their ideas publicly on the class white boards (pictures below).  The ideas were labeled as possible hypothesis statements.  Students then had to select the hypothesis they believed to be the most correct and then wrote a conclusive statement explaining their understanding of the science behind the hypothesis statement.

IMG_6558IMG_6559IMG_6560IMG_6561IMG_6562

We followed that with a video:

After the video, students received the first draft of their conclusions back for more focused editing.  Slides 3 and 4 of the attached slide deck helped the students focus their scientific writing on clearly articulating the claim, evidence, and reasoning for their revised conclusion.

End of Course, Energy, Matter, Organization

Energy, Matter, and Organization: Writing a Scientific Conclusion – Day 2

Leave a comment

Lots of writing today.  We began class with an entry task in which students were instructed to describe the trends in the data found in the graph on page 2 of yesterday’s case study.  Students were provided with the sentence frame:

Plants grown in _____ hours of light increased/decreased in height over _____ weeks.

After some private think/write time, students shared their work with their table partner.  Students selected at random were asked to publicly share their learning by writing an assigned trend sentence on one of the class white boards.  After we reviewed the example trend sentences for plants grown in 0, 12, 17, or 24 hours of light, students were provided with an EOC-style conclusion worksheet (page 2).  Students had 20-30 minutes of silent write time, and students who finished early were encouraged to exchange papers with a friend and look for the 5 elements on pages 4-5 of the conclusion worksheet packet.

End of Course, Energy, Matter, Organization

Energy, Matter, and Organization: Writing a Scientific Conclusion – Day 1

Leave a comment

Welcome to second semester!  It was nice to see everyone, and I look forward to a second half of the year equally as full of learning as the first half.  Today we turned our sights to the Conclusion section of a scientific lab report.  Writing a conclusion statement requires higher-level analysis and is a skill all students should master.  Additionally, the Biology End-of-Course Exam will test the ability of students to write a scientific conclusion statement.

After starting off the lesson with a nuts-and-bolts slide, students read through a fictional scientific experiment case study.  I had the opportunity to read through student lab reports from the Baggie Garden experiment this weekend, and there were a few common recurring items that required addressing.  The case study was written to include the following:

  • An incorrectly written research question
  • A hypothesis statement not directly connected with the research question
  • Many clearly defined controlled variables
  • A graph with data that conflicts with students’ experience from class

After reading through the case study, students publicly identified the research question (bottom of page 1), the hypothesis (first paragraph of page 2), and the experimental variables (manipulated, responding, and at least three controlled).  We will continue our work tomorrow, with students using their learning to write a conclusion statement.