Hot and Cold

This week we learned how to use a thermometer. First we measured some temperatures in and around the kitchen: the freezer, the fridge, room temperature, etc. Then we went out into the yard to find the hottest and coldest spots. We were surprised to find as much as a 5 °C difference between sunny and shady areas.

Slippery Slope

Which surface has the most friction with a coin?
To figure this out, we placed a coin on top of different materials, gradually raised one end of the material until the coin began to slide, and measured the angle using a protractor. The idea being, the steeper the angle necessary to get the coin moving, the greater the friction between the material and the coin. 

Next week we hope to apply our results to the larger question: What can you do to reduce the friction on playground slides? Let's hope for good weather!

Slime flies when you're having fun

How to make slime that has just the right consistency - neither too sticky, nor too watery?
It's all in the measuring...

Over the past few weeks, we've learned how to measure liquid volumes using a graduated cylinder, how to measure mass with the digital scale, and how to mix different colored water to make a rainbow of possibilities. This week we put these skills to good use making the ultimate SLIME! 

Tipping the scales

Do you have too many skirt hangers lying around?

In the mood for cream of mushroom soup?

Wondering what weighs more: a daffodil bulb, a AA battery, or a vertebra from a wild bore*?

Then I've got the perfect DIY project for you!

This week we learned about mass. Each lab group built a scale using a skirt hanger with an empty mushroom package suspended at each end. We compared the masses of various small objects by placing them inside the baskets. Finally we checked ourselves using a digital scale.

* a daffodil bulb

The Tortoise, The Hare, and You!

Usain Bolt is unquestionably the fastest human alive, but how would he do if he had to compete against other species, like say a grizzly bear? In 2009 he broke the world record, running 100 meters in 9.58 seconds. That's faster than 10 m/s and around 38 km/h. This week we looked at some data on the maximum speeds of different animals and then tested our own local humans.

Most of us fell somewhere between a chicken and a pig.

Can you weigh and chew gum at the same time?

Did you ever wonder what happens to the mass of gum as you chew it?

To investigate this question we used a scale to measure the mass of the gum at one minute intervals. Now, I know what you're thinking...how does one chew gum and weigh it multiple times without being REALLY gross?!  Bubble gum wrappers make great weighing paper, so we just made sure to measure the mass of the gum in its wrapper before and after chewing it.  Still a little gross, but nothing our scientists couldn't handle.

After graphing the data we observed that the mass decreased, and surprisingly, it didn't happen at a constant rate. Most of the sugar was lost in the first 2 minutes, and after that there was relatively little change. After analyzing our results we wondered if bubble-blowing and talking might affect our results.

Water, water, everywhere!

When it comes to space exploration, nothing makes the news quite like the possibility of finding extra-terrestrial water. Just over a month ago,  a research team from Japan used the Subaru Telescope to observe the water-rich atmosphere of Gliese 1214 b, a planet 40 light years from Earth.

Why are we always searching for water in space? What does discovering water have to do with the possibility of discovering extra-terrestrial life? 

To begin answering these questions, we explored some of water's interesting properties through the following investigations:

Water's molecular structure: We made models of water molecules, noting how oxygen and the 2 hydrogens share electrons.

Water sticks to other water molecules and other stuff too: We observed the U-shaped water line in a graduated cylinder and the dome shaped water line, as you fill a cup just beyond the brim.

Water is strangely denser than its solid form, ice. 

Water's a great solvent: We saw how water dissolves marker ink and carries along its components through filter paper.

Finally we discussed why these properties are so important for life as we know it.