Sunday, August 21, 2011

DISCUS breaks 50 lesson plan mark!

DISCUS now has 50 and counting K-12 science lesson plans, free and available for use by science teachers.  Lessons cover many different topics and all grades.  All lessons have gone through our rigorous peer-review process to ensure quality.  They feature a 5E format and incorporate a multitude of sheltered instruction teaching strategies.  This format is ideal for effective instruction of a diverse group of students and includes elements that make science fun and interesting for everyone.  Search lessons to see if there is something you can use. Build your own lessons and share your ideas with others.  Thanks to all of the teachers who have contributed to DISCUS thus far.  We look forward to more great things to come!

Wednesday, July 27, 2011

Casein Glue

We all know how it happens... you are right in the middle of an arts & crafts project and you run out of glue.  It can be so frustrating, but did you know that you probably have all of the things around your house that you need to make your own glue?  Here's how to do it.

What you need:  Glass jar (e.g., an empty pickle jar), metal pot (for the stove), water, nonfat milk, thermometer (a cooking thermometer will work well), white vinegar, a funnel, baking soda, a spoon, and an eye-dropper.

[Caution:  This experiment involves boiling some water on the stove.  Ask for a parent's help or permission to carry out that step.  As always, it is a good idea to where some safety glasses (maybe your parents have some from their home improvement projects you can use) when performing experiments.]

What to do:  Fill the metal pot half-way full of water and bring to a boil.  When the water boils, remove from heat.  Fill your glass jar almost 2/3 full with milk, and then fill the rest of the way (~1/3) with white vinegar.  Place the glass jar into the hot water bath and insert the cooking thermometer into the mixture of milk and vinegar.  Stir gently with the spoon, until the mixture reaches 60 degrees Celsius (140 degree Fahrenheit).

Once the mixture reaches 60 degrees C, use the funnel to filter off any liquid (the whey).  The whey can be discarded.  Retain the curds and transfer back into your glass jar.  Putting a paper towel in the funnel can help you separate the curds and whey more effectively.

Next, stir in 1/2 teaspoon of baking soda (sodium bicarbonate) to the curds.  Slowly add drops of water and stir until the mixture retains the consistency of standard white glue.  Once you have reached that point, your glue is ready to use!

How does it work? Milk contains fat, protein, and lactose, with a normal pH between 6.3 and 6.6.  At this pH, the protein in milk remains dispersed.  However, when the pH is lowered by the addition of an acid (vineagar = 5% acetic acid), the net charge of the proteins change and they begin to clump or aggregate.  The proteins clump together into casein, an insoluble mass, which precipitates out of solution.  This the curd that you separated from the whey.  The excess acid in the filtered curds is then netrualized by the addition of a base (baking soda = sodium bicarbonate = NaHCO3).  After that, you have casein glue!

Now, get back to those arts & crafts...plenty of glue to go around.  Thanks to Rebecca Denney at U.T.  Arlington for submitting this project to DISCUS.  Very cool one!

Thursday, July 21, 2011

Electromagnetic Motor!

So, it's hot, and you are bored at home, or in need of a science fair idea, but you only have a battery, a magnet, some copper wire, pliers, and wire cutters.  Well, that's enough to make a simple homopolar motor.  A homopolar motor is a simple motor which uses a electromagnetic field to work.  It was invented in 1821 by Michael Faraday (if you have never heard this name, look him up...he did some really impressive things!).  This project is safe, fun, and easy to will definitely impress your family and friends.

What you need:  You only need five things - a battery, a magnet, some copper wire, some wire cutters, and pliers to shape the wire.

What to do:  Cut a length of wire and use the pliers or your hands to shape it in various ways.  Be creative.  After you try your shape out, you can alter it, and try again to see what shapes work better than others.  It is good to have some type of central point in the shape that you can align with the top of the battery, and to make sure that the shape is long enough to reach down to the magnet.  Now, center the battery on the magnet (the negative pole of the battery should rest on top of the magnet).  Balance the copper wire shape on top of the battery.  Make small changes in the shape until it spins freely.  Feel free to develop the experiment by changing the size of the battery, the magnet, and/or the copper wire.  See what shapes spin fastest.  If you need some help, or just want to see the motor in action, check out this You Tube video put together by Nham Tran, a U.T. Arlington undergraduate chemistry major, who submitted this project to be featured by DISCUS.

How does it work?  One word - electromagnetism.  In this experiment, the battery provides the electircal current and the magnetic provides the magnetic field.  The combined current and magnetic field creates an electromagnetic force.  When the wire is balanced on the battery, the current travels into the wire and down to the magnet.  The electromagnetic force generated causes the wire to spin.  It will spin indefinitely, until the battery dies.

Have fun and tell us how it worked for you!

DISCUS breaks 1000 registered users!

We now have more than 1000 registered K-12 teachers, parents, and students registered on the website and using all of the great free resources we have available.  Thanks to all of our current registered users! If your not yet a member of DISCUS, and you have any relationship to K-12 education (even if it is just your kids in school), then we have something for you.  Everything is free and we will never share your information with outside parties.  Join now to receive access to great at-home science activities, higher education opportunities, links to useful and fun programs, great lesson plans (for teachers), and quarterly newsletters.  Join the more than 1000 users of DISCUS now!  Visit to register and see what we have for you.  If you think there is something missing, let us know, and we will be happy to add it (email

Thursday, June 23, 2011

Middle School Chemistry from the ACS

An excellent resource was brought to my attention.  It seems that the Office of K-8 Science at the American Chemical Society has created a similar resource to that available through DISCUS.  Middle School Chemistry features a whole course full of 5E middle school level chemistry lesson plans, as well as a range of multimedia resources.  We all need to work together to increase scientific literacy in the United States.  This will only be done by using best teaching practices to reach the broadest range of students possible.  Kudos to ACS for their contribution in this regard.  And thanks to Elisa Rice at U.T. Arlington for bringing this great site to our attention.

Sunday, May 1, 2011

Can a White Man Speak with Authority on Diversity? (DiversityInc)

I, the founder and director of DISCUS, will not hide the fact that I fit the mold of the majority population in the United States, as it is defined in Luke Visconti's article on "Can a White Man Speak with Authority on Diversity?".  While I have certainly perceived my efforts to be valid and important, I have often wondered how this effort would be perceived by everyone else.  Mr. Visconti's words ring true to me, in that there are many levels to diversity.  Diversity is an awareness that, in order to achieve the best of anything, it should be perceived from many different viewpoints.  That is why it is so very important that all of our nation's students, regardless of background or heritage, take up the task of pursuing scientific literacy.  While all will not become scientists and engineers, all will need to interact with and understand science and engineering to some degree in their lives.  Even better, the more students who can be engaged and excited by science and math, the more chances our society will have to excel.  We should all have in our mind the importance of science, but to have the biggest impact, science should also be intertwined with diversity.  Thank you for supporting our efforts with DISCUS.

Monday, April 11, 2011

Why Chemistry Matters on

Chemistry, especially in the media, sometimes gets a bum rap.  That's too bad, and a notion we as a society of scientists need to change, because everything in the world around us is chemistry.  From the food you eat, to the clothes you wear, to the gas in your car, to the cell phone in your pocket - there is virtually nothing that chemistry isn't an integral part of.  More Americans need to realize this.  That's why it is so great to bring a series of videos, called Chemistry Matters, to your attention.  These are short videos, aimed at students, which have the goal of communicating the importance of chemistry to our life. Check them out.  They are very interesting and thought-provoking for virtually anyone at any grade level.

One Nobel Laureate expounds, "If there is any one subject that an educated person should know in the world, it is chemistry."  For us here at DISCUS, it is hard to disagree.  Thanks to Meg Young, chemistry teacher at Lamar High School in Arlington, TX, for bringing these videos to our attention.