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Candace Chick is the first to admit that she’s not an expert in science. Far from it, the teacher at the Samuel W. Mason Pilot Elementary School in Roxbury, Mass., only took one basic science class during her undergraduate and graduate studies and, until recently, quaked at the idea of teaching the properties of matter to her fifth-grade students. “I have always been insecure about science,” she says. “It is not one of my strengths.”
But now, she is positively ebullient about the progress both she and her students have made in the subject. Her class has been investigating molecular change, conducting hands-on experiments, and watching computer simulations. The students’ knowledge has grown deeper than simply being able to define terms like “condensation” and “evaporation.” They readily discuss their ideas and frequently engage in polite, intellectual arguments that influence each others’ learning. “Their knowledge isn’t, ‘Oh, there is a puddle on the sidewalk and when the sun comes out it evaporates and goes magically into a cloud and then it comes down again when it rains,’’’ Chick explains. “They understand how those molecules start to move and bounce around like mad as they evaporate. They really understand this in a way that they didn’t before.”
Chick’s class just completed the third year of a research endeavor called The Inquiry Project, a partnership between teachers, TERC, and Tufts University that teaches concepts like weight, volume, and density in grades 3–5 to lay the foundation for later introduction to molecular theory. In third grade, students begin exploring materials and then move on to investigating weight and volume, using density cubes and balance scales, among other tools. They proceed from comparing the “felt weight” of cubes made from different materials to measuring actual weight on a balance scale. They ask questions along the way. Can two objects of the same size weigh different amounts? Does a tiny piece of clay have weight? The students are asked to discuss their findings at every step: the goal of this “productive talk” is to lead to deeper understanding.
Chick worked with an Inquiry Project coach, who not only helped her overcome her inhibitions about science but also encouraged her to lead productive class discussions.
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The goal is to shift the students’ way of thinking from what Anderson calls “force-dynamic reasoning” to what he terms “scientific discourse.” Force-dynamic reasoning, typical in elementary school, is a way of viewing the world in terms of “actors” with purposes. For instance, the main purpose of a tree (the “actor”) is to grow, and in order to grow, it needs water, air, sunlight, and soil. However, the scientific explanation is that the tree uses the sun as an energy source to convert carbon dioxide and water into glucose, which is the building block of the tree. “The scientific story is one of transformation of matter and energy,” Anderson explains. “If we are interested in preparing kids to think about carbon in our atmosphere and in our various environmental systems and how it effects global warming, we have to make the transition from force-dynamic reasoning to scientific reasoning, where they are thinking about matter and energy.”
The fourth-grade curriculum outlines a pathway toward that transition in thinking. It’s not about memorizing definitions of, say, photosynthesis, but about actually transforming how students think. Students begin by watching time-lapse videos of plants growing. They then grow plants under different conditions—with or without water and light. They measure the results over time and ultimately determine that plants need water, air, and light to grow. They then examine plants on a microscopic level and learn about their cellular makeup, which leads to an exploration of how plants make their own food and where they store it.
Through tending the plants and watching them grow, students can begin to view the plants not as actors, but as part of an ecosystem. Anderson and his colleagues are still generating data on what works, but the goal is for the students to understand basic underlying principles of science, such as conservation of matter and energy. “Facts alone,’’ he says, “are not enough.’’
Learning Progressions in Science
By PATTI HARTIGAN
Harvard Education Letter
Volume 26, Number 4
July/August 2010
I'm wondering what exactly these 4th grade students know about photosynthesis at the end of the school year.
14 comments:
And we wonder why other countries are doing better at educating their students. If we have non-scientists developing non-scientific programs that do not teach science, we will eventually end up with? (Answer: Non-scientists that have grossly distorted beliefs about science). But maybe everyone (teachers included) will feel good that they taught nothing and students learned nothing about science.
“Facts alone,’’ he says, “are not enough.’’
It's amazing how this can be translated into "scientific discourse" and hands-on learning.
"They then examine plants on a microscopic level and learn about their cellular makeup, which leads to an exploration of how plants make their own food and where they store it."
What, specifically, are these facts and how are they learned with "scientific discourse"?
I was expecting much worse.
For the grade levels discussed, this isn't so bad. At least they're learning about molecules.
There is no need for students to actually grow plants under different conditions in order for them to learn about plants' needs for water and light. That is a very inefficient way to convey that knowledge. Not to say that it all has to be about learning facts from books; but there are plenty of chances to observe these realities that don't involve the time investment of starting dozens of plants from scratch and varying their environments.
Considering that science in the early grades is nonexistent or poor, it won't take much to improve it. If you screw it up, there is still time for the student to get back on track. This is not true with math. For many kids, it's all over by 7th grade, and they can eliminate a career in science too.
It doesn't say anything good about ed school that only one basic science course is required. BTW, as first-graders in the mid-50s, my class learned parts of plants, plant nutrition, photosynthesis, heliotropism etc. Why am I not surprised that global warming is part of this curriculum? I also agree with the last comment about the inefficiency of this approach, but efficiency seems to be fighting with mastery for last place in the pantheon of ideas that concern the ed system.
Yeah, I'd completely agree with SteveH. Elementary science education is bad, but not the priority.
I'm also not a fan of the fetish of "hands on" science in early grades. Demos can be effective, or lectures. With little kids, it is mostly a matter of having a straightforward point to make.
For a few years, I was doing a regular science lesson once a year in my mother's kindergarten class. I came in one day and taught for ~40 minutes, but the one idea I wanted to impart was something that they remembered even a year later. I taught them a little about oxygen, that it was part of the air, and that they needed it to live. Then we did a really simple demo -- if you light a candle in a pan of water, and cover it, the candle goes out once the oxygen is consumed, and the water rises into the newly empty space. They loved it, and would have had me do it ten times in a row, and they remembered the basic idea that oxygen was part of the air. But a lot of elementary education types would dismiss this as not inquiry and not hands on.
All that said, this article doesn't bother me too much. In a lot of elementary classrooms now, they don't do any science at all, or just environmental stuff.
I agree that science does not have the essential, sequential nature of math, but it is part of the background knowledge that is essential in reading comprehension, so I do feel that it should be part of the curriculum from the beginning. Done right, teaching this material doesn't have to take a lot of time. I agree with chemprof about a well-designed demonstration by a knowledgeable teacher being better than hands-on by kids - and is a vastly more efficient method.
"I'm also not a fan of the fetish of "hands on" science in early grades. Demos can be effective, or lectures. With little kids, it is mostly a matter of having a straightforward point to make."
Little kids are so gosh darn distractible. While I don't think that growing plants is necessarily such a bad thing, I wouldn't expect a lot of scientific knowledge to come out of it, unless accompanied by very firm guidance.
What is taught (or what adults believe is being taught) is not necessarily what is learned. A year or so ago we took the kids (the oldest 6, the younger almost 4) to San Antonio and stayed a block from the Alamo. We heard a gripping lecture on the history of the Alamo and did the River Walk as well as a children's museum and a carriage ride and a mission church. We all had a good time. What did my oldest take away from the experience? 1. She remembers the Rainforest Cafe where we ate twice. 2. She was impressed by the cartoon cable channels on the hotel TV. So, unless a teacher is careful, what children are focusing on may be something totally irrelevant.
I've seen kids at various hands-on science museums and the only ones who even appear to have a clue what they're seeing and doing are the ones (1-3 kids) who have a parent right next to them, explaining the point of each experience. Even small school groups, with an adult, don't seem to be concentrating well. The constructivists seem to be happy with the appearance of learning, and care less about the reality
This sounds similar to elementary science programs from Singapore that I have used. In contrast to US programs that are usually vocabulary intensive, the Singapore programs use an approach that is more concepts and systems oriented, eventually requiring kids to develop pretty sophisticated understanding. This level of conceptual understanding is akin to Singapore's math programs, and indeed, math programs like TERC Investigations were actually trying to imitate Asian math programs. Unfortunately, they failed miserably because they also tried to remove the "pain" and "tedium" of learning. I suspect that a TERC science program would go the same way.
"I've seen kids at various hands-on science museums and the only ones who even appear to have a clue what they're seeing and doing are the ones (1-3 kids) who have a parent right next to them, explaining the point of each experience. Even small school groups, with an adult, don't seem to be concentrating well. The constructivists seem to be happy with the appearance of learning, and care less about the reality"
Amen. I think the worst offenders are the really loud science museums where it's all ZAP!, POW!, DING!, FLASH! The kids run around pushing buttons to make things happen, and there's no learning whatsoever. Quieter children's museums are less headache-inducing, but are often no more educational.
ChemProf, can you explain to me why the reaction
C_k H_{2k+2} + (2k+1)O_2 ->
k CO_2 + (k+1) H_2O
results in a loss of volume of the gas?
Is it due to condensation of the water vapor? Would burning charcoal produce no change in volume?
Telling the kids that it is "consumption of oxygen" seems misleading.
Right, the water vapor forms hot, but then condenses as it cools to room temperature (and since we perform this reaction over water, the air inside the container is already saturated with water.
If you burnt pure carbon completely, so the reaction is C + O2 -> CO2, then yes, the volume of gas wouldn't change.
However, this assumes nice complete consumption, which you don't have under these conditions. Instead, we are forming some CO2, some CO, and a lot of soot. So most of the volume loss is indeed due to oxygen consumption. With middle school kids, I'd write the reaction and talk about the products, but with kindergarteners, if I can get them to know that air has different components, that's good enough for me.
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