Archive for the ‘Best Practices’Category

Back to School with Discrepant Event Science!

After a restful summer (which included a move to a new school!), classes are finally back in session! I always begin the year with a set of activities that challenge students to practice science process skills (observing, recording data, asking questions, etc.). My approach includes a series of quick “discrepant event” demos that captivate (and baffle) my students. From trying to figure out why two ice cubes melt at dramatically different rates to brainstorming explanations for how a sealed opaque balloon suddenly starts self-inflating, these demos engage students, assess students’ science skills, and emphasize the processes and habits that scientists use to inquire about the world around them.

Asking Questions

My first demo begins with two black plates upon each of which I place an ice-cube. Within seconds, students notice a difference between what is happening to the ice cubes. As a puddle forms around one cube, the other remains solid ice showing now signs of melting. I then ask students to record two questions, the answers to which they think will help them understand the difference between the two ice cubes. Students share their questions (Are the ice cubes both made of the same substance? Is one plate hotter than the other?) and explain why they the answers to their questions will help them more fully understand what’s going on. After a few minutes of sharing (but not answering) questions, one student invariably suggests moving the not melting cube to the other plate. When it begins melting and students exclaim that it must be that the one plate is hotter than the other, I pass around the plate sitting under the rapidly melting cubes. To students surprise, it is not warm but instead ice-cold! We continue the discussion and questioning, eventually discovering that the plates are made of different materials (wood vs. metal) and discussing conduction and relative temperature. In this 20-minute investigation concludes with a discussion of how asking questions helped us (and scientists) understand an unexpected phenomenon.

Ideas & Resources

My discrepant event introductory lessons typically include five different demos, each practicing a different skill (recording observations, asking questions, recording data, making predictions, etc.). Below are some of the materials I use in my classroom and resources on how to bring discrepant event science into your classroom.

Brain-Powered Science 

From NSTA Press:  Author Thomas O’Brien created his Brain-Powered Science series for educators who love to surprise and challenge their students with unanticipated results. Using his inquiry-oriented experiments based on the science of discrepant events—hands-on explorations or demonstrations in which the outcomes are not what students expect—teachers can challenge students’ preconceived ideas and urge them to critically examine empirical evidence, draw logical inferences, and skeptically review their initial explanations with their peers.

Ice Block Demo – As described and pictured above.

Self-Inflating Balloons – A sealed, opaque mylar balloon mysteriously begins to self-inflate

Two-Balloon SurpriseTwo balloons are connected by a valve. When the valve opens, the smaller balloon inflates the larger one.

Happy & Sad Balls – A ball suddenly stops bouncing after being secretly switched for one made of a non-elastic material

UV Detecting Beads – Beads change from colorless to vibrant colors, but only in some types of light.

Sinking & Floating Spheres – Two spheres with identical masses respond differently when placed in a bowl of water

Astro BlasterA red ball mysteriously bounces five times higher than the height from which it was dropped.

 

17

09 2011

Rube Goldberg Machines (Innovative Ideas Video!)

 

In 1990, I created a 14-step machine that, after 2 minutes of toppling dominoes, cascading marbles, and straws sliding down makeshift zip lines, popped a balloon. Inspired by the cartoonist Rube Goldberg, I entered my machine into the Ingenuity Challenge 300, a science & technology competition held to celebrate the 300th anniversary of Schenectady, NY, the town where I grew up. I remember the excitement when I finally got all of the carefully engineered steps to work… and the thrill of winning 4th place in the county-wide for my balloon-popping device.

Over twenty years later, the Rube Goldberg project has become an integral part of my teaching, serving as a culminating assessment for my 8th grade physics unit. Students apply their understanding of Newtonian physics to create 8 or more step machines that include 5 or more different simple machines. After presenting their finished machines to their families and younger students, my 8th graders engage in a detailed written analysis of their machines and a reflection on the engineering process. I find this project to be particularly powerful for how it pushes students to not only apply content knowledge but also to think critically, problem solve, and work collaboratively.

Students presented their machines just yesterday (my classroom is filled with K’NEX towers, marble ramps, dominoes, and Lego contraptions – all to accomplish tasks like pulling a tissue from a tissue box, stirring a glass of lemonade, or ringing a bell). To share some of my successes with this project, I’m posting the lesson plans and student materials that I use to guide students through the construction process. The downloadable materials include a rubric to assess student work and ideas for how to best implement the process in your classroom.

As a new feature on The Science Guru blog, I’m also posing a video from my classroom in which I share tips on implementing the project with your students. Please share your successes and challenges – post a comment, send me an email, or post your own video response. Good luck and happy engineering!

Rube Goldberg Project Download

01

06 2011

Innovation at the STEMposium

In the last few years, STEM has become a buzzword in the education community. STEM, which stands for Science Technology Engineering & Math, has developed out of a growing concern that the US education system is not effectively preparing the next generation of innovators. From the National Science Teachers Association centering their 2011 around STEM education to the countless tech companies developing seeking to engage students in critical thinking with innovative curriculum centered around technology, STEM’s focus plays an important role in rethinking and reforming education.

Recently, the California Academy of Science, in partnership with several education organizations, foundations, and companies, held the “STEMposium” in San Francisco, CA. This event sought to bring together innovators in education to share their successes and best practices in STEM education. From a PIXAR animator working to bring animation and programming into schools to a Librarian reinventing the classic science fair using the web to a science teacher having her students build smartphone applications, the winners and finalists of the STEMposium are truly bringing innovation to how we engage our students. Visit the STEMposium website to learn about each of these inventive projects.

10

05 2011