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Physics Education Technology - University of Colorado, Boulder
PhET Blog

Learn Why Things Float with the Buoyancy Simulation


When you can’t go to the pool, learn why things float with the Buoyancy simulation. Arrows show the applied forces, and you can modify the properties of the blocks and the fluid. Apply what you learn next time you’re at the pool.


Aug 2


Play in the Snow with Our Glaciers Simulation


Looking for a fun educational way to cool off? Adjust mountain snowfall and temperature to see the glacier grow and shrink in our Glaciers simulation. Use scientific tools to measure thickness, velocity and glacial budget.


Jul 29


See PhET in a Swedish Television Series on STEM Ed

Swedish TV Series on PhET

Last April, we hosted a Swedish TV film producer and crew that were interested in featuring the University of Colorado’s efforts in STEM education in a 30-minute episode for a Swedish television series on education. While the narration is in Swedish, the interviews with Founder, Carl Wieman, CU professors, and students are in English. See PhET in action at CU in the classrooms.

Here’s a link to the special that was aired on May 10, 2013 in Sweden:

“Is there a democratic classroom? Carl Wieman works to improve science education in the United States. At the University of Colorado scientists show that active learning, combined with new pedagogical tools give better results. Through web-based interactive tool, students can simulate the lab at their computers. Carl Wieman says, much of the science that is taught in the classroom allows students to sit with their brains turned off, while the teacher takes care thinking.”


Jul 22


Keep Math Skills Fresh with Fraction Matcher

Fraction Matcher

Want to keep those maths skills fresh over the summer? Try Fraction Matcher sim. Match shapes and numbers to earn stars in this fractions game. Students can challenge themselves at different levels, collecting stars as they improve their fraction skills.


Jul 16


Java 7 Incompatibility


On June 18, 2013, Oracle released Java 7 update 25 (1.7.0_25), which introduced an incompatibility that prevents PhET simulations from launching when using either the “Run Now” button on the website or the PhET Offline Website installer.

Oracle has fixed the problem and the fix should be available in the next version of Java (although this new version may not be released for some time).

Until this problem has been resolved, the best work-around for users experiencing this issue is to “Download” local copies of the simulations. When you press the “Download” button on a sim page, a “.jar” file will be downloaded. You can then double click the “.jar” file to run the sim locally. (Please note: on a Mac, you will have to right-click the “.jar” file and select “Open.”)



Jul 10


Healthy Eating with Our Eating and Exercise Simulation

Eating and Exercise

With summer fun here, explore how many calories are in your favorite summer foods and how much exercise you’d need to burn them off with the Eating and Exercise simulation.


Jul 3


NSF Highlights PhET on Their SEE Innovations Site

The NSF Logo

Read about how PhET Makes Learning Science Fun on the National Science Foundation’s Science, Engineering and Education (SEE) Innovations website.

“The PhET project’s main goals are to make science accessible, understandable and fun. In the new ‘Build A Molecule’ simulation, for example, students learn as they play. They discover that collections of atoms create molecules; that the number, type, and order of the atoms matter; and that the ‘twos’ in 2CO2 mean different things. Students build connections that provide a key foundation to understanding chemistry–connections between chemical names, chemical symbols, atomic arrangements and molecule shapes. In a recent study, fifth-grade students using the simulation demonstrated that they had learned these ideas–ideas that have been documented as difficult even at the college level.”


Jun 27


PhET in the Philippines

PhET Simulations are used not only in the United States, but also around the world. Rollan Inis from the Tagum City National High School in Tagum City, Philippines writes that Philippine teachers from remote “barangays” will be using the offline installation of PhET to “teach science in a very interesting manner.” In addition, PhET was used at a Grade 8 teacher training program held by the Department of Education.

Thanks Rollan for spreading the word on how PhET can enhance science and math learning in schools around the world.

Do you have a story on how PhET sims are being used? Please e-mail Kathy at


Jun 21


PhET is Now in Wikipedia

PhET Interactive Simulations is now on Wikipedia at

We worked on the article through a Peer to Peer University School of Open Education Program:Peer to Peer University/Writing Wikipedia Articles. Thanks #WIKISOO for helping us get PhET into Wikipedia.


Jun 17


Support PhET During Our End-of-School Campaign

Even though school’s ending, PhET will be hard at work over the summer upgrading the simulations for the new school year. And, right now, user donations are our key source of funding towards converting simulations to HTML5 and bringing them to iPad and Android tablets. So please help support our summer vacation work and give the gift of learning.

Donate today. And, thank you to those of you who have already donated. Your support will help keep our work funded through the summer.


Jun 11