Audacity

If you're recording a song or narrative, here's a link to software called Audacity. It's free and legal and very popular. If you want to try to remove the vocals check out this youtube clip. It really only works sometimes. Your best bet is to find and download the instrumental track to a song.

Remember, the project is due on Wednesday, June 3.

Testing is almost done, time for your final project

Only one more day of testing. You've worked hard and we're down to less than a month of school.

Monday I'm assigning your final project and it's called....Create Your Own Project.

Briefly: Create, design, make, build anything that shows your knowledge of 8th grade science. Your grade will be based on the level of knowledge you choose to represent. Check back later examples.

Clara and Abigail

Hi everyone,

Here's a pic of my new daughter, Clara, and her big sister, Abigail. See you next week!

Balancing equations

If you would like to demonstrate 4.0 level knowledge for the Periodic Table you will need to know how to balance equations. If you still need help, this website is really good. It has really helpful practice problems at the bottom.

New Topic - Periodic Table

We have a new topic - the Periodic Table. For a list of what we're learning check the wiki. Here's a link to a website that has videos on each element. It's called the Periodic Table of Videos.

Trimester ends Friday!

This week is your last chance to bring up your scores for our three topics for this trimester. The three topics were Forces and Newton's Laws, Floating and Sinking, and Atoms.

If you wish to bring up your scores, the easiest thing to do is to check the document named trimester2summary.doc on the wiki page. It will list what standards you should learn to achieve certain scores. It also has a list of sample questions. It's never too late to earn the grade you want.

Acids and bases

Your goal for this section is to be able to tell the difference between an acid and base. In class, we used pH paper to find the pH of different mystery liquids. From there, we matched the pH of the mystery liquids to the pH of known liquids, like vinegar and ammonia.

All matter is made of atoms.

Sorry for the large gap between posts. Our school's web filter has decided to block blogging sites. It makes it difficult for me to publish the class content online.

We started a new topic on atoms. The big idea is that everything is made of atoms. We've been learning about the kinetic molecular theory. That's a fancy way of saying that atoms are always moving and bumping into each other. When those atoms are heated, they speed up. Since they're speeding up, they move farther apart. Heat them up really quickly and you get really fast expansion as you can see below.




The molecules of air in the film canister were rapidly heated and spread out quickly. This blew the film canister into the air.

Another implication of the KMT is that molecules bump into things and cause pressure. In this picture you see a balloon in a bell jar. The vacuum pump (not pictured) removes the air from the jar. The air inside the flask remains. It is still moving around and there's pressure inside the balloon. Since the pressure inside the balloon is greater, it expands. Remember when we learned how to calculate net force? Same idea. Since the pressure is greater on the inside, it expands until it reaches equilibrium.















That's it for now. Remember that the trimester ends in two weeks. If you are unhappy with your current grade, check your portfolio and find out what you still need to learn.

Forces concept map

Here's a link to the concept map I showed in class.

http://prezi.com/6634/

To zoom, just click. If you want to go back, hit spacebar. All of the things we've been learning about since November are linked to the basic concept of forces. Keep that in mind as forces will keep coming up again and again.

Density and Buoyancy

Our unit on floating and sinking is coming to a close. Remember that in standards-based grading, your grade is based on your content knowledge. It is never too late to improve. To jog your memory, here are two recent activities we've done in class.

We built and sunk aluminum foil boats. In the first part, we built a small, medium, and large boat. Then we put pennies in them until they sunk. Using our triple beam balance and graduated cylinder, we found the mass and volume. Using the formula: density = mass/volume we were able to find the density.

In part two, our task was to design boats that would hold a minimum amount and then sink. For example, the first boat needed to hold 15 pennies and sink by the time it got to 20. By finding the mass of 15 pennies, we were able to predict the volume the boat would need to be. This time we built a boat using the formula: volume = length * width * height.

Today we created rainbow density columns. The goals was to create a liquid rainbow in a graduated cylinder using only food coloring, sugar, and water. The less dense liquids floated on top of the more dense ones. Here are some examples.

Rocket video

Here's an animoto video of our rocket project. Turn up the volume and enjoy. The song is Paper Planes by M.I.A. It's a satire about the way people stereotype immigrants, but I think the chorus is perfect for our paper rockets.

Why do things float or sink?

We have just completed an experiment investigating why things float or sink. Students filled film canisters with various weights. The students found the mass when the film canister sunk, floated, and was at neutral buoyancy. They used water displacement to find the volume of the film canister. Here's the data from 15 of the groups.


Averaging the data we got a mean mass for the sinking items as 50.6. For floating items it was 16.8. For neutral items the mass was 40.5. The average volume we found was 40.2

Students then created a rule based on the data. It appeared that the objects where their mass was greater than their volume, they would float. If the mass was less, it would sink. If it was the same, it would be neutral.

The relationship between mass and volume is called density. It is the key topic we will be studying for the next two weeks.

Final rocket due tomorrow

Remember to bring your final rocket tomorrow. Here's a video from our last test launch. It wasn't the rocket that went the highest but it landed right next to me so I think that's worth a post.

Inertia demonstrations

Welcome back to school and I hope everyone had a wonderful holiday break. I took my family to the Monterey Bay Aquarium and the California Academy of Sciences.

Just before we left for vacation we filmed demonstrations on inertia. Students created their own demonstrations from objects from home or around the class and wrote a script to explain the demonstrations. Below are three examples. Don't forget to turn up the volume.










In case you can't hear the videos, all objects need to have a net unbalanced force exerted on them in order to speed up, slow down, or change direction. In the first example, the student exerted a force on the index card so it accelerated forward. The washer would have stayed stationary forever, but the absence of the card holding it up meant that there was a net unbalanced force (gravity) that pulled it down. It would have kept falling down forever, but the table exerted a force on it to stop it.

If you want a copy of your video, email me and I'll send it on.