We did a bunch of different activities today. Since we just had the eclipse I decided to have them do a month of lunar observations. They put the moon observation pages in their notebook and went outside to sketch the moon for their first data point. We’re actually taking a break from class for a few weeks (vacation, yeah!) so this will give them something to do until we’re back. The moon observation pages are from the Universe at Your Finger Tips DVD, which I’ve mentioned many times before and can also be found online.
Earlier this week, students watched movies from Unit 3.1 on the Big History Project website, about the elements and how they come from stars. About half the students in this class have been in my classes for many years, so I know their science background. But half the kids are new this year, so I decided to give a short presentation on atoms and elements incase they hadn’t covered it, plus it doesn’t hurt to repeat material. I don’t remember where I got the blank atom templates, have used them many times over the years. I asked the kids to pick a number between 1 and 18 and tell them that’s the number of protons their atom has, and to write it in the middle of the atom. Then we used the Element Card deck to determine how many neutrons they needed for their atom and to determine what element they had. Then they filled in the electrons, starting with the inner most shell. A few of the kids remembered doing this before and were excited to see this activity again, and also disappointed we only did one. When we did chemistry a few years back they each made one or two and then had to compare their atoms to other student’s atoms and find one they could bond with. Today I just asked them what they thought it meant if the atom’s electron shell was full and got answers of ‘happy’, and ‘stable’, which were excellent answers since atoms with full shells are inert and very happy all by themselves. We pulled out the element cards for those atoms with full shells and discovered they were all noble gases, some of the kids already knew this and shouted it out – remember this is a class of mostly 12 and 9 year olds. I was really happy with what the kids remembered from previous years.
The other activity in the photo above was from the Big History Project and involved putting pictures of a star’s life cycle in order in their notebook. After talking about the elements, we watched this video from Sci Show Space on how we are made of star stuff.
I also talked about how there are approximately 200 billion stars in the Milky Way Galaxy and we tried to wrap our minds around that huge number. Again, this activity came from the Universe at Your Finger Tips DVD. I had a cubic centimeter box that I made from paper and had filled with grains of sand. I asked the kids how many of grains of sand they thought were in the 1 cubic cm box. Some said 100, some said a million and one got it just right, 1000. How do I know there was 1000 grains of sand? I counted them! …. Well, I started to count them and after I had 10 piles of 10 grains of sand I started just making piles of about the same size and came out to roughly 950 grains of sand in my little box. To make life easy, this is an estimation after all, we went with 1000 grains of sand. Then I showed them a cube that was 10 cm on a side and asked how many grains of sand would it hold. One kid was really on the ball and immediately shouted 1 million, which was correct. This still isn’t even close to 200 billion so then we talked about a box 1 meter on a side, 1 cubic meter, and now we’ve got 1 billion grains of sand. So I asked them if 200 billion grains of sand would fit in my house, most said no, so I made them measure my house. I only had two meter sticks to split among 12 kids so they had to devise some great ways of estimating the distance. We found that yes, 200 billion grains of sand would fit in my house, but it would be a layer almost 2 meters high! So all those grains of sands, filling my house, represent the number of stars in our galaxy… mind boggling. And of course that’s only one galaxy in the universe! I held up one grain of sand and said if this is a star, how far away does the next grain of sand have to be to model the scale of the galaxy. Some answered, the other side of the house, the driveway, the next town… its about 60 km (40 miles) between grains of sand representing stars. The Universe is a lot of empty space.
The other thing we did today was look at sun spots…. well, sun spot. There was only one ‘tiny’ sun spot visible. I used a pair of binoculars to project the image of the sun on a poster board. You can NOT look through the binoculars at the sun, it will damage your eyes, but you can use them to project an image. We do this to look at solar eclipses and transits as well. The kids held up a piece of paper against the board and traced the sun and the sun spot and taped it into their notebooks. If you look very closely a little to the lower left of center you’l see the sun spot. I’l set this up another day when there is more activity.