Drive Systems

With another short week, we'll just get part way through investigating drive systems.  Thank you to Mrs. Rylander who brought in a whole bag of lids for us!

Drive Systems are when single wheels are used to transfer energy from one part of a device to another.  There are a few ways they can be aligned.  There is the wheel-to-wheel drive system.  Here if one is turned clockwise, the other turns counter-clockwise.  The two wheels can be moved apart, making it a belt drive system.  Depending on the alignment of the belt, the wheels can be made to turn the same direction or opposite.  For both types, if the wheel has cogs, we know it better as gears.



Mechanical advantage can be created when one wheel is larger than the other.

This is best explained by thinking about a multi-geared bicycle.  If you need advantage to go up a hill, you'd switch gears so that the chain goes on the largest cog on the rear tire.  This allows you to keep your pedals turning even if your rear tire is not rotating that fast.  If you want the advantage of building speed, you'd switch the gears so that the chain goes on the smallest cog on the rear tire.  This allows you to pedal slower but have your rear tire go faster!

Pulley Week; January 29

Pulley Week-
Knowing we were short a few days this week, we worked hard to focus our attention on this week's question:  What are pulleys? and How do they give us Mechanical Advantage?

Simple Pulley

Movable Pulley

We assembled a fixed pulley, learned how it makes work easier; we are able to lift the load by pulling toward our core (easier with our body's skeletal and muscular build).


We assembled a movable pulley, and using a fish scale, learned that although we no longer lift by pulling toward our tummy, this assembly actually decreases the necessary force by half!

Block and Tackle

Checking out the fish scale's reading on the fixed pulley

This culminated in combining the two. . . into a block and tackle assembly.  Now, we get the mechanical advantage of both- pulling towards our tummy, and needing only half the force of the load.  Check out your child's kidblog post where they were to describe their findings.



Next week - drive systems!  If you have drinking containers with the small plastic lids, would you mind collecting them and sending them in?  Thank you!

*all images from Wikipedia Pulleys

Weekly Update; January 17

Wow, it's the middle of January already!

Here is a quick summary of our Science program so far. . .

Our Drink Car Dragster; time to add wheels.

We had a late start to our regular schedule in the fall, but when we did get going, we started right into our Waste in our World Unit.  The main points in this unit were for students to develop an awareness of how nature has no left-over waste; waste will either become food for other organisms, or will decompose and become nutrients for the plant kingdom.  This then ties to all the types of waste that we humans produce, and what we, as a society, try to do with it.  Our unit culminated with a 'Making a Difference' project  that the students really enjoyed working on!  Unfortunately, December raced by, and we didn't quite finish these to be able to present, but the students were very engaged in the message they wanted to include in their project, which is what my main focus is.  The students filled in a planning page for this which can be found in their Google Drive account.  If you haven't yet, ask you child to show you their Drive account, and what work they have in there already.

Time to test with wheels

That brings us to our new unit: Simple Machines.  This is a two part unit, the first includes the theory in how simple machines such as wheels and axles, pulleys, drive systems and levers make work easier, and the second is applying this theory in a series of building challenges.  It is a great hands on unit!  I have two requests:  the first is that we will be using a lot of materials that are found in household recycling.  I'll keep you posted on various items we may be needing, and if you are able, we'd appreciate you sending it in to school, and the second is if you are able to come visit during our class to man the glue gun, or help with other tools such as hammers or screw drivers, I would really appreciate it! We have an hour at the end of every Monday, Tuesday, and Thursday; just let me know!

More testing

Our first building project is to add wheels to a pop can to measure the distance without wheels compared to with wheels.  Our results were mixed, partially due to the lack of stability of paper wheels!  The conclusion is that adding wheels will decrease the friction, allowing the car to go further!  Next week, we will build a paper chassis, and add a wheel/axle combination using straws, skewers, and, yes, more paper wheels.  The students will need scissors, if they've lost them, please send in a replacement pair!

Thanks for visiting;

Mrs. Kiss

Making a Difference Project

Project time:

We started planning for our project today.  The kids are excited to create their Movies!

Here are the sites that we'll be using:

1.  Padlet - a brainstorming site.  The kids have posted many ideas on here already that they can refer to when planning their project.

2.  Kidblog - the students are welcome to review previous posts to get ideas for their project

3. Google Drive - this is where they will find their planning document.  They'll need this filled in and approved before they start taking pictures.

4.  Binders - I know, not a site. . . but still; lots of valuable information there!  

Later this week, we'll talk about what programs are available that they can use to make their finished movies.  I'm excited to see what they come up with!