Growing Spheres Help Students Absorb Scientific Principles


John Fedors, Educational Innovationsby:  John Fedors

Hydrophilic spheres from Educational Innovations offer a variety of interesting applications and opportunities for scientific inquiry. They come in a variety of sizes: regular, jumbo, & gigantic. For the following examples, I prefer the regular or #710 size. However, whichever size you choose, they will expand to about 300 times their original dehydrated size.

Growing SpheresAs they absorb the water, they become almost invisible, due to having the same refractive index as water. When placed in de-mineralized or distilled water and kept away from sunlight, they will dehydrate to their original size and can be re-used. Dehydration time will depend on air humidity.

Once enlarged, these clear spheres can be used to demonstrate:

* The lens of an eye (such as those of a shark, calf or sheep) that has the ability to magnify the print on a page. A thin slice may be used to mimic a cornea transplant.

* The suspension of small items such as a coin.

* Roots of a germinating seed.

Enlarged growing spheres can also help to observe the relationship of Surface Area (A=4pr2) to Volume (V=4/3pr3) mass in grams. They can be used to graph relationships. Read the rest of this entry »


What is a Radiometer?


Tami O'Connor, Educational Innovationsby: Tami O’Connor – Taken From Litetronics

The radiometer is a light bulb-shaped device containing an object that looks like a weather vane (wings arranged in a circle like spokes of a wheel).  Developed to measure the intensity of radiant energy, or heat, the radiometer will:

  1. Help you understand the principles of energy conversion.
  2. Show how heat and mechanical energy are products of energy conversion.

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Demonstrating Density: Who Knew They Could Be So Dense?


Tami O'Connor, Educational Innovationsby:  Tami O’Connor

Density is not typically an easy concept for most middle school students and even more difficult for younger students, but it doesn’t need to be.  We all know that D=m/V, but the easiest way I found to explain it to my students was to have them visualize a common dilemma in my home immediately preceding a vacation.  For years, as a poor starving teacher, I only had one suitcase, and it was actually a hand-me-down from my mother.  It was a medium sized Samsonite, hard cased piece of luggage.  When approaching the topic of density in my classroom, down from the attic it came.

My explanation began with an imaginary week-long summer vacation to a low-key resort.  The class and I would brainstorm the items I needed to pack for my trip.  Generally, the list included items such as a few bathing suits, shorts, t-shirts, a pair of flip flops, some PJs, underwear and a few toiletries.  It was obvious by looking at the size of my suitcase that in addition to my meager belongings, I could have probably also fit one of my students in my bag…  ok, perhaps one of the smaller kids.

I explained that when I closed the suitcase, it was hard to see, simply by looking at it, how heavy it was.  The lesson didn’t stop there.  We now planned my one-week ski vacation to Vermont during the February break.  Once again, my students and I made up my pack list.  The list included a couple of heavy sweaters, long johns, gloves, a hat, boots… as you can imagine, the list went on and on.  The question was, where to put it all.  Of course, since I had only one suitcase, the answer was easy. Read the rest of this entry »


Two Prisms: Four Demos


Marty Sagendorfby: Martin Sagendorf

Most everyone knows that an equilateral prism will refract white light into its constituent colors: a spectrum ranging from red to violet.  But, if one uses two prisms, there’s much more to be discovered.

All that’s required:

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Gro-Beast Alligators


Jill BrownBy : Jill Brown

Each year I purchase the Gro-Beast Alligators from Educational Innovations for my Fourth Grade class.  These growing alligators start at about three inches long and grow to over a foot long when placed in water!  From this one item, I have developed lesson plans that incorporate Math, Science, Reading, Social Studies, Writing, Technology, and Language Arts!Gro-Beast Alligator

Observation is the first action taken by learners to acquire new information about an organism; therefore, the first thing my students do is observe their polymer alligator.  The students in the picture below are in the process of measuring the length, weight, circumference, and area of their polymer alligators. Students in my class also trace their alligators on graph paper then they calculate the area of each and eventually compare the area of their small (dehydrated) alligator to that of their fully grown alligator. (Math & Writing & Language).  These measurements are compiled into a line graph for each student’s crocodile which aids students in making predictions about the rate of future growth of their growing reptile.  Read the rest of this entry »