Air Pressure: Suction Cup Drink Holder

Education Innovations sells these neat rings that work like a suction cup to hold your drink. 

You slide a can or bottle into the ring, set it on a smooth, flat surface and it sticks! 

While not terribly expensive, it's simple enough to make your own version.  You'll need a flexible, stretchy material.  I've found that the plastic jar grippers, sometimes given away by companies, work well.

The original Lil' Suctioner has a radius of just over 2 inches.  While I wouldn't go smaller than that, it certainly wouldn't hurt if yours was bigger. 

Cut about a one inch hole in the center of your material. 

Slip the material over a can or bottle and test it out for yourself. 

By the way, the Lil' Suctioner includes some air pressure facts, including the weight of the atmosphere pushing down on it (~221 lbs).  But, there's no reason you can't figure it out for your own drink holder.  If it's a circle, measure the radius; if it's a rectangle, measure the length of the sides.  Make all measurements in inches. 

Calculate the area of your material (for a circle: pi x radius x radius; for a rectangle: side x side) and multiply that area by 14.7 psi (pounds per square inch).  That will give you the number of pounds of the atmosphere pushing down on your drink holder, of in other words, the pounds of force you'll have to exert to lift up your drink.

Website: HowToSmile.org

I recently learned of a new (brand new to me, fairly new in general, I think) website filled with science (and math) activities: HowToSmile.org.

Currently, most of the activities on the site come from the collections of various hands-on science museums (The Exploratorium, Science Museum of Minnesota, Lawrence Hall of Science, etc.). 

I particularly like that you can create your own lists of activities - create one list of everything that looks interesting or create several lists and sort activities by topic, grade level, priority, etc.  Possibly even better than that, is the ability to search other people's lists.  I tend to find the most exciting ideas by looking at what other people have deemed worthy to add to their lists. 

Speed/Velocity: Which Goes the Fastest?

Here's a fun way to practice speed calculations. 

Gather a bunch of self-propelled vehicles.  They can be wind-up or ones you have to pull back and release.

Use masking tape to make a starting line and a finish line 1 meter apart.

Wind up (or pull back) the vehicle and place it at the starting line.

Let go and start a stopwatch.  Time how long it takes for the vehicle to reach the finish line.  Record the time and determine the speed the vehicle travelled. 

The obvious unit to use in this activity is m/s, but you may want to challenge some of your students to covert it to other units: m/h, cm/s, etc. Or, really test them by having them convert to miles/hour!

Genetics: Easter Egg Genetics

Students use plastic eggs to practice their Punnet square-solving-skills. 

Each egg color has been assigned a genotype:

• Blue - BB
• Green - Bb
• Yellow - bb

(This example uses incomplete dominance - i.e. Bb appears green, not blue, as it would in a straight dominant/recessive situation). 

The eggs have been mixed and matched to create various genetic crosses.  For example, a blue half matched with a green half would represent BB x Bb. 

Students use a Punnet square to solve the cross, and then open the egg to check their work. 

Teacher Notes:
This activity has nothing to do with Easter, but the eggs are only available at that time of year.  Check your local grocery store, big-box store, drugstore, etc. at the end of the month for eggs on clearance.  Get them now, and you'll have them for whenever you want to do the activity.

The original activity, Easter Egg Genetics, is part of the Access Excellence Activities-To-Go Collection.  If you visit the original, you'll find a guide for filling all of the various egg combination, which will save you a few minutes of precious time. 

http://www.middleschoolscience.com/ has a student worksheet to accompany the activity (and she also includes the egg-filling guide with her teacher notes), which can be found here. 

You can fill the eggs with appropriately colored candy, which is a lot of fun if you are giving each student one (or maybe 2) eggs as a quick assessment.  If you want each student to work their way through more eggs (and you don't want the hassle of refilling the eggs), use appropriately colored objects - counting chips, pieces of construction paper, centimeter cubes, etc.  The students can replace the objects after they check their work and you're all set for next time.

Energy: Nuclear Fission Demonstrations

While we're on the topic of explaining nuclear energy, you can find some recorded nuclear fission demonstrations on YouTube. I know many schools have blocked YouTube, but I hope it's still useful to some of you.  

My favorite video comes from Touchstone Energy.  While not recorded for scientific purposes, the sheer size of the demonstration is impressive.  You'll have to ignore the sales pitch, but it's non-offensive and pretty short. 



And, just for fun, here's another commercial video along the same lines. 

Energy: Understanding Nuclear Energy

I may be a bit late in getting this to you, but hopefully it's useful to someone out there....

In light of recent events in Japan, or just in the course or your curriculum, you may be looking for ways to help your students understand nuclear energy. 

I just stumbled across this publication, Nuclear Experiments You Can Do, from the Charles Edison Fund..

The pdf file includes simple models/demonstrations for splitting an atom and chain reactions, as well as more
advanced demonstrations related to nuclear energy and radioactivity.

I wanted to pass this your way as quickly as possible, since it is a timely topic.  As a result, I haven't looked through the other experiments available, but they could very well be worth taking a look at.

Website: Middle School Science Yahoo Group UPDATE

A month or so ago, I told you about the Middle School Science Yahoo Group and since that time I've discovered another fabulous aspect of the group, which I had completely missed previously. 

If you've take some time to look at the group, you've realized that you can read the messages people post without being a member. 

But, you'll also notice there are some things reserved for Members Only.  One of those things is access to the Files. 

When you join the group, you'll magically gain access to those Files, and some other things as well. 

And once you're in, you'll find folders and folders willed with lessons, activities, templates and more that others have created and uploaded to share with anyone in the group. 

If you've been on the fence about whether to join or not, I highly recommend you do, both to access such a knowledgeable, supportive online community and the materials they're willing to share.  And maybe you've even got something you're willing to share with the group in return!