Science for 5th Graders
October 22, 2009 9:23 AM Subscribe
Help me influence the future of science - or- I have no idea how to finish my student teaching lesson.
So, I'm supposed to teach my lovely 5th graders (20 of them) about concentration and saturation using this Foss kit. Easy right? Well, yeah, except the main teacher taught the lesson when I wasn't there. Now I'm supposed to re-teach it on a deeper level without a.) Going too deep and surpassing their understanding and b.) Not boring them to death with a rehashed lesson. So hive mind, help me out! Since my mentor teacher told me they had some trouble with the concept of concentration, I was thinking of doing something with colored powders or sugars, so they could see the concentration level (ie, darker is more concentrated than lighter). I think this could work well, but I don't know what powders to use that I can easily color. Would colored sugar work the same way (I know how to dye that!)? Thanks for your help in getting kids to love science!
So, I'm supposed to teach my lovely 5th graders (20 of them) about concentration and saturation using this Foss kit. Easy right? Well, yeah, except the main teacher taught the lesson when I wasn't there. Now I'm supposed to re-teach it on a deeper level without a.) Going too deep and surpassing their understanding and b.) Not boring them to death with a rehashed lesson. So hive mind, help me out! Since my mentor teacher told me they had some trouble with the concept of concentration, I was thinking of doing something with colored powders or sugars, so they could see the concentration level (ie, darker is more concentrated than lighter). I think this could work well, but I don't know what powders to use that I can easily color. Would colored sugar work the same way (I know how to dye that!)? Thanks for your help in getting kids to love science!
Colored powders: KoolAid packets contain basically sugar plus food coloring.
Note: human vision is nonlinear, so don't be surprised if a solution that's half as concentrated as another doesn't look exactly half as dark.
posted by Quietgal at 10:08 AM on October 22, 2009
Note: human vision is nonlinear, so don't be surprised if a solution that's half as concentrated as another doesn't look exactly half as dark.
posted by Quietgal at 10:08 AM on October 22, 2009
Both these ideas could work. As a bonus, the kids could potentially drink the KoolAid (yeah, yeah, obvious jokes) and taste the difference in concentration as well as see it. Which might reinforce the lesson
As well as the chair idea (which is nifty), you could just make a space in a corner of the room and have more and more students go into it to show concentration -- you might be able to go beyond that by talking a bit about osmosis and equilibrium. (Alton Brown does a version of this in the pork chop episode of Good Eats, but he makes the kids wear "salt" and "water" hats...). Unless you are doing osmosis later.
posted by GenjiandProust at 10:14 AM on October 22, 2009
As well as the chair idea (which is nifty), you could just make a space in a corner of the room and have more and more students go into it to show concentration -- you might be able to go beyond that by talking a bit about osmosis and equilibrium. (Alton Brown does a version of this in the pork chop episode of Good Eats, but he makes the kids wear "salt" and "water" hats...). Unless you are doing osmosis later.
posted by GenjiandProust at 10:14 AM on October 22, 2009
My thoughts also jumped to KoolAid. Lab safety procedures permitting, in addition to a visual demonstration, you could also have them taste the drinks - a fully saturated glass will taste a lot different than a glass with a low concentration of sugar/flavour. Maybe the taste stuff could also be extended to a bit of an anatomy discussion (if you're meant to "deepen" their understanding of the concept) - talking about taste buds, etc. (not sure if this is part of the Grade 5 science curriculum where you are).
You could do 4 glasses:
1. Fully saturated (some visible powder not disolved)
2. High concentration
3. Low concentration
4. Just solvent (water)
posted by purlgurly at 10:21 AM on October 22, 2009
You could do 4 glasses:
1. Fully saturated (some visible powder not disolved)
2. High concentration
3. Low concentration
4. Just solvent (water)
posted by purlgurly at 10:21 AM on October 22, 2009
Best answer: First, colored sugar wouldn't be a perfect indicator. The sugar and the dye will have different levels of soluability and affect the results. It might be good enough for 5th grade, but it will be something they will have to un-learn when the lessons get more detailed. Better to use a more pure demonstration- simply dye and water. This liter of water has three drops and is this color, this other liter has ten drops and is way darker.
I would do two things:
1- Pre-quiz (doesn't count against them), or pre-instruction question and answer session, so you can gauge what they know and don't know.
2- Using the black board or some other visual demonstrator, show what the concept of concentration really is.
You don't need to go into the deep, dark specifics, just a light primer on structure and soluability. I doubt they need to know the specifics of polar molecules and all that jazz.
"A solid is when the molecules are locked together. A fluid is when they are attracted together, but can still move about. A gas is when the molecules are just floating along. This happens because of two competing forces- the desire for the molecules to be close to other like molecules, and the energy in the system, which causes the molecules to want to be further apart. Every element has different temperatures, but what is the same is this: when something is solid, there isn't enough energy to make the molecules pop apart. When something is a fluid, there is a sort of balance of energy and attraction- they still want to be together, but they also want to be free. When something is a gas, there is so much energy in the system that the molecules just dance around, almost completely unattracted to each other."
"Soluability is when you can mix two fluids together and they can't be separate out. When something is soluable with another thing, and you mix them together, this is called dissolving. Some things won't dissolve at all- like oil and water. You can mix them up, but you end up with a mixture of tiny globs of oil and water. Or like sand and water. In both cases, all you have to do is wait for them to separate. This means they are insoluable."
"Some things are very soluable with each other, so that you can mix any proportion of them together and they will not separate out. [example- maybe alcohol and water? I forget]"
"And a lot of things fall in between. They are soluable, but only to a point. At some point, the attraction of the water molecules won't let any more of the other stuff in. When you have a solution that is completely full, this is called saturated."
"And, it depends on the temperature of the fluid as far as how much stuff can be put in. That's why it is easier to dissolve sugar in hot tea than iced tea. [maybe here you can do a quick illustration of the molecules in a hotter solution being further apart, letting more stuff in.] If you take a hot solution, and dissolve something in it until the point of saturation, and then you cool it off, that is called a super-saturated solution. This means that it is unstable, and is just waiting for something to come along and let it get back to normal."
"And so the concentration is the ratio of the one thing to the other, or the solvent to the solute."
If you have the equipment, I would do this: get two of those hot plate/stirrer machines. One of them is not heating, the other is heating to maybe 180 degrees. Put in sugar in equal amounts to each, showing how the sugar dissolves more and more slowly. When the cold one won't take any more, keep adding to the hot one until it won't take any more. With the cold one sitting next to it, still not completely dissolving.
Then you can warm up the cold one and show how it takes up the sugar when it gets warmer.
Then dump off the solution from the hot one into a new container, and let it cool to room temperature. Hopefully, it will remain super-saturated, and you can drop in a grain of sugar, or even tap the side, and show the sugar come out of solution. Disco.
(Since I had a dream about being trapped in High School last night, let me relate my experience as a student being taught by student teachers. They were almost always terrified, but refused to acknowledge it in class. The only thing more cruel than high school students being assholes to a new teacher is high school students being cruel assholes to a new teacher who tries to pretend s/he isn't new. 5th graders should be nicer- but I would posit that it's way easier to maintain control of a classroom when you treat the students with enough respect to let them in on the "secret" that you're new. You cede no authority doing that. Also, don't make the mistake of pulling the "you better be nice to me or I'm telling your real teacher" threat. Never worked, in my experience.)
posted by gjc at 10:24 AM on October 22, 2009
I would do two things:
1- Pre-quiz (doesn't count against them), or pre-instruction question and answer session, so you can gauge what they know and don't know.
2- Using the black board or some other visual demonstrator, show what the concept of concentration really is.
You don't need to go into the deep, dark specifics, just a light primer on structure and soluability. I doubt they need to know the specifics of polar molecules and all that jazz.
"A solid is when the molecules are locked together. A fluid is when they are attracted together, but can still move about. A gas is when the molecules are just floating along. This happens because of two competing forces- the desire for the molecules to be close to other like molecules, and the energy in the system, which causes the molecules to want to be further apart. Every element has different temperatures, but what is the same is this: when something is solid, there isn't enough energy to make the molecules pop apart. When something is a fluid, there is a sort of balance of energy and attraction- they still want to be together, but they also want to be free. When something is a gas, there is so much energy in the system that the molecules just dance around, almost completely unattracted to each other."
"Soluability is when you can mix two fluids together and they can't be separate out. When something is soluable with another thing, and you mix them together, this is called dissolving. Some things won't dissolve at all- like oil and water. You can mix them up, but you end up with a mixture of tiny globs of oil and water. Or like sand and water. In both cases, all you have to do is wait for them to separate. This means they are insoluable."
"Some things are very soluable with each other, so that you can mix any proportion of them together and they will not separate out. [example- maybe alcohol and water? I forget]"
"And a lot of things fall in between. They are soluable, but only to a point. At some point, the attraction of the water molecules won't let any more of the other stuff in. When you have a solution that is completely full, this is called saturated."
"And, it depends on the temperature of the fluid as far as how much stuff can be put in. That's why it is easier to dissolve sugar in hot tea than iced tea. [maybe here you can do a quick illustration of the molecules in a hotter solution being further apart, letting more stuff in.] If you take a hot solution, and dissolve something in it until the point of saturation, and then you cool it off, that is called a super-saturated solution. This means that it is unstable, and is just waiting for something to come along and let it get back to normal."
"And so the concentration is the ratio of the one thing to the other, or the solvent to the solute."
If you have the equipment, I would do this: get two of those hot plate/stirrer machines. One of them is not heating, the other is heating to maybe 180 degrees. Put in sugar in equal amounts to each, showing how the sugar dissolves more and more slowly. When the cold one won't take any more, keep adding to the hot one until it won't take any more. With the cold one sitting next to it, still not completely dissolving.
Then you can warm up the cold one and show how it takes up the sugar when it gets warmer.
Then dump off the solution from the hot one into a new container, and let it cool to room temperature. Hopefully, it will remain super-saturated, and you can drop in a grain of sugar, or even tap the side, and show the sugar come out of solution. Disco.
(Since I had a dream about being trapped in High School last night, let me relate my experience as a student being taught by student teachers. They were almost always terrified, but refused to acknowledge it in class. The only thing more cruel than high school students being assholes to a new teacher is high school students being cruel assholes to a new teacher who tries to pretend s/he isn't new. 5th graders should be nicer- but I would posit that it's way easier to maintain control of a classroom when you treat the students with enough respect to let them in on the "secret" that you're new. You cede no authority doing that. Also, don't make the mistake of pulling the "you better be nice to me or I'm telling your real teacher" threat. Never worked, in my experience.)
posted by gjc at 10:24 AM on October 22, 2009
Response by poster: My thoughts also jumped to KoolAid. Lab safety procedures permitting, in addition to a visual demonstration, you could also have them taste the drinks - a fully saturated glass will taste a lot different than a glass with a low concentration of sugar/flavour. Maybe the taste stuff could also be extended to a bit of an anatomy discussion (if you're meant to "deepen" their understanding of the concept) - talking about taste buds, etc. (not sure if this is part of the Grade 5 science curriculum where you are).
You could do 4 glasses:
1. Fully saturated (some visible powder not disolved)
2. High concentration
3. Low concentration
4. Just solvent (water)
I'm liking this idea, so should I do the same flavor in each glass with just various amounts of mix? I'm thinking that would work the best as I'm trying to reinforce the importance of one only having one variable.
posted by julie_of_the_jungle at 10:27 AM on October 22, 2009
You could do 4 glasses:
1. Fully saturated (some visible powder not disolved)
2. High concentration
3. Low concentration
4. Just solvent (water)
I'm liking this idea, so should I do the same flavor in each glass with just various amounts of mix? I'm thinking that would work the best as I'm trying to reinforce the importance of one only having one variable.
posted by julie_of_the_jungle at 10:27 AM on October 22, 2009
That's what I was thinking - my vote would be for grape (just because it's my favourite flavour :).
gjc does also have some good thoughts - I'm still a fan of the tasting though, even though it's not a perfect illustration (the kind of "science lie" that we were probably all told throughout elementary and secondary school :) because some kids may not remember the visual, but will remember the tastes.
posted by purlgurly at 10:42 AM on October 22, 2009
gjc does also have some good thoughts - I'm still a fan of the tasting though, even though it's not a perfect illustration (the kind of "science lie" that we were probably all told throughout elementary and secondary school :) because some kids may not remember the visual, but will remember the tastes.
posted by purlgurly at 10:42 AM on October 22, 2009
What's the important science here? In college they might learn that the solute stops dissolving once entropy is no longer increased in doing so. A chemist would learn this process at a deeper level, considering how multi-atom molecules dissociate in acids. A physicist learns about this rate equation. A biologist learns about ion pumps, and "hypotonic" solutions where there is less salt on one side or the other. And... people who cook or stir coffee need to know that sometimes there will be stuff left over.
What useful things can we teach to kids?
1) Proportional amounts of solute dissolve in proportional amounts of solvent. I like the chair ideas above.
2) Some things dissolve less in different fluids. You could measure by eye the amount of powder left, after being stirred into orange juice or some alternative liquid/powder set.
3) Dissolving is temperature-dependent. Probably more safe to use ice instead of heating.
On viewing your link, it looks like this is the point of the experiment... Which is all to say, make sure they reflect on the conclusions instead of just thinking they spent the day playing with koolaid.
This isn't too helpful, but I'm posting it anyways.
posted by gensubuser at 11:55 AM on October 22, 2009
What useful things can we teach to kids?
1) Proportional amounts of solute dissolve in proportional amounts of solvent. I like the chair ideas above.
2) Some things dissolve less in different fluids. You could measure by eye the amount of powder left, after being stirred into orange juice or some alternative liquid/powder set.
3) Dissolving is temperature-dependent. Probably more safe to use ice instead of heating.
On viewing your link, it looks like this is the point of the experiment... Which is all to say, make sure they reflect on the conclusions instead of just thinking they spent the day playing with koolaid.
This isn't too helpful, but I'm posting it anyways.
posted by gensubuser at 11:55 AM on October 22, 2009
Response by poster: In case anyone was wondering I thought I'd post a follow up. We're going to have 3 cups with 3 different solutes and find the concentrations and saturation levels of each cup. I made a nifty little worksheet to go with it that you can see here.
posted by julie_of_the_jungle at 10:45 AM on October 28, 2009
posted by julie_of_the_jungle at 10:45 AM on October 28, 2009
Response by poster: Err... here rather.
posted by julie_of_the_jungle at 10:47 AM on October 28, 2009
posted by julie_of_the_jungle at 10:47 AM on October 28, 2009
This thread is closed to new comments.
posted by Good Brain at 9:48 AM on October 22, 2009