Friday, February 28, 2014

Brush Bots 2014

I taught another after school class for fourth and fifth graders with brushbots again this year.  The kids really seem to enjoy making them.  We had a few issues with defective parts this year, although in some ways that is okay.  The kids learn how to debug the circuit when things don't work as anticipated.

If you haven't made these before, brush bots are a lot of fun to make and pretty easy.

  First of all  you need a motor, DC 1.5-3 volt with leads attached or a spot to attach wires.   You will also need a way to unbalance the motor, and here I have used an alligator clip.  There is a chance that the clip will fly off and could potentially hit someone, but we haven't really had problems with that.

I like to wire in a switch so you don't have to pull the battery to get the brushbot to stop.  Here I have a slide switch, but  I have to say I like the toggle switches better.

Finally, you will need a power source, a AA battery and a holder.  The holder enables the student to change the battery themselves and keep their brushbot in working order.

The parts that I have links to have worked pretty well with no real  issues.  I did order some directly from China from another distributor, and I have had several of the parts not work.  

I have the kids wire these circuits themselves and use electrical tape to keep everything together.  I don't think turning fourth graders loose with a soldering iron is all that smart.  I have enough trouble with glue guns!

Now, you just need to mount the circuit onto a brush, and let them go.  Initially, I have the kids tape them onto the brushes and move the components around until they move they way they want them to.  Then, it helps to fix them into place with a glue gun.  And, you can decorate them if you want.  These are great fun.  Just be warned, the glue gun is a great tool, but a HUGE distraction with the boys.  They seem to like to glue lots of things other than the parts.

 You can also build in some learning at the same time if you want.  I will be doing that in a couple of weeks as I work this project in my teaching at a local school.  We will start with the idea of atoms, electrons, building a battery, then onto circuits.

Friday, February 7, 2014

Kindergarten Toy Designers

Today we had the kindergartners build toy vehicles that used magnets as "engines".  Given a cup, a doughnut magnet, popsicle sticks, life savers, straws and tape the kindergartners were challenged to build a vehicle that they could "push" around with a wand magnet.   All the students jumped in with great confidence and glee.  All were successful and had great fun driving their vehicles around the classroom.

I love challenging the students to these types of fun exercises because it gives those students who don't normally construct things a chance to try out a new activity.  And for those students who excel at hands-on activities, it gives them a chance to shine.

Tuesday, February 4, 2014

STEM Workshop for Teachers

I ran a workshop for teachers a couple of weeks ago.  I have been trying to get this post up, but we had a week off of school due to snow and frigid weather.  Then, our pipe burst, but now the kids are back in school, the work is being done on the house to repair all the damage and I am trying to get this posted.

I presented a bit of background information, then we went into the why's and wherefore's of teaching engineering design to elementary school students.  There are those who are of the opinion that we should not be teaching kids any type of "engineering" because they are too young and it is just a dumbed down idea of building stuff.  However, I am of the mind that kids love to make things, and yes, all right, they can't design a bridge that would meet the safety codes for use on a highway, but we can give them the tools and excite them about how the science they are learning in school can be used and is used everyday all around them.  So, what is the harm in having them pretend to be engineers?  I think it would be so much better to have them pretend to be engineers than supermodels or secret agents.

So, why do we want to use hands-on engineering type problems to teach children science concepts?  Just think of the following study of the retention of students presented with material to learn:

§10% retention with reading only
§26% retention with hearing only
§30% retention with seeing only
§50% retention with seeing and hearing
§70% retention with seeing, hearing, and repeating,

§90% retention if learner saw, heard, repeated or said something about topic, and used ideas 

 (You can find more about these ideas in *Teaching Engineering, Wankat and Oreovicz, McGraw-Hill, 1993, Chapter 15, “Learning Theories”.)

      So, a hands-on experience can give a student a 90% retention of the ideas presented because they will have seen the material, heard the teacher talk about it, then they will repeat or talk about it among themselves and will think and use the ideas in their assigned activities.  This is only a bit of what I covered, but one of the most important points, I think.  After finishing the presentation, I gave the teachers a chance to have fun with a hands-on activity themselves.  I challenged them to think like a Greek or Roman and build a simply support bridge.  Their challenge was to build a bridge holding the most coins.  I used nickels simply because they weigh 5 grams each and are easy to count for most young students (2nd and 3rd graders).  (Just for your information, pennies weight approximately 2.5 grams which is a bit more of a challenge for calculating weight.)  For the first part of the challenge, the teachers could use only one sheet of paper a bit of tape and no other tools.  For the next challenge, they can use a fresh sheet of paper but scissors in addition to more tape.  Here are the teachers having fun with their challenge.  I must say the activity got a bit competitive between the teams!

I did see quite a few approaches to the challenge.  The most common approach was to fold the paper, but you can see that one group tried a fan approach and another group used the idea of the covered bridge design.  I encouraged them to think like Greeks and Romans, but no one used the idea of columns in their designs, but all had fun and it encouraged them to think of new ways to get the students engaged.  

I am looking forward to hearing about how they will include hands-on design activities in their classes in the coming months.  

If your school is interested in a fun workshop about STEM and design in the classroom then please contact me.