There are of course many basic concepts that are important, but I think the most important skill to teach is how to apply the scientific method. Students need to learn how to formulate questions and then design experiments to test them.

I find that the basic concept is sometimes lost in the sea of vocabulary words that young students have to memorize.

This is a really tough question, but an issue about which I'm pretty passionate. So, here's my best attempt to answer from my heart:

First of all, to get an idea of what all kids are expected to know, take a look at the National Science Standards, which you can find on line pretty easily through Google. This at least will give you an idea of what the National Science Foundation thinks that kids should know, but it is based on a model of teaching science every year, for 12 years - an ideal that, unfortunately, many states and schools don't follow.

I understand that it is now extremely difficult, in California at least, with all the language standards that are being imposed on the public schools, to teach science. But on the other hand, I can understand that if you can't communicate with the kids because of the language problem, that you can't teach them anything. So it is a tough problem.

But, even with the imposition of all the reading requirements, you can still teach science if you see it not as a collection of facts, but as a way of life. So, if you want to know what I personally would like for all kids and people to know, it is that science is NOT a just bunch of facts, but how to look inquisitively at everything!

However, since you have asked, "What fundamental, basic science facts should all People know?" I would say the most fundamental "fact" that I would like people to know is our place in the Universe - Where the Earth is in the solar system, why we have seasons (NOT because the earth is closer to the sun in summer! - see A Private Universe video) and where the Sun is in the galaxy, and the relationship of the galaxy to the universe.

I would like people to look up at night and recognize the Milky Way as the galactic plane. I would like people to recognize Sagittarius and Scorpios and point between them and exclaim, "That is the direction of our galactic center, where lurks a super massive black hole, about 30 million times as massive as the Sun!"

But that is all. Other than knowing our place in the universe, there are no "facts" in physics - other than the dates when key discoveries were made, and papers published. Everything is an observation, an interaction with the world. To even ask the question of what "facts" in science should people know puts science in the corner where it does not belong, that of being perceived as just a collection of facts.

Science is a way of life, a way of looking at the interaction with the world in which we live, and a love and respect for it. How does one teach this? By example; it is an attitude and an outlook, and is developed by teaching kids to be aware of their surroundings, to ask questions, to be curious about everything. You point things out to them, take them on walks and show them the stars; you drop things and watch them fall, play with floating things in the bathtub.Even with no "time" in the curriculum, there is always a moment here and there to look at something and ignite curiosity.

Kids are infinitely curious. So, what I want kids to "learn" in school about science is that it is a path of inquiry and respect, an attitude towards life, within a certain conceptual framework; NOT a collection of important facts that every educated person (in the western world, anyway) should "know". In this spirit, I can finish answering your question. Here are some concepts and attitudes that I would like for all kids to acquire, and carry with them as adults in their lives: I would like people to understand that everything evolves, the universe, stars, people, animals - but this is NOT contradictory to believing in God, and that NO where in the Bible are any dates given, other than the ages of some of the leading characters, and that the Creation story is an allegory, a way of ancient people trying to understand their place in the universe. And they were not far off! First there was some sort of "void" (the vacuum state); then there was light; then matter and radiation separated; eventually stars evolved and finally people appeared on Earth. I want people to understand that scientists and spiritualists are not enemies, but are trying to understand the same phenomena from different points of view, and as long as we don't insist that we "know" how long a "day" is in the allegory of the Bible, that we are not disagreeing with each other. So, basically I want kids to learn TOLERANCE. As science teachers, this is one of our biggest challenges.

I want people to know what a THEORY in science really is. A theory is a WORKING MODEL that explains observations, and allows us to make predictions with a fair bit of accuracy.

Good question, and a hot one, too. I can imagine that this very question has been the focal point of countless vigorous discussions at all levels of participation, from the federal government through school boards and PTA associations down to the students themselves. Certainly the lack of proper scientific understanding among our students, and in society in general, has been greatly lamented, but what to do about it?

This debate is likely to fall within the broader question of what to do with our failing educational system in general. To be honest with you, I'm very concerned with the lack of scientific knowledge present among our students, but I'm far more concerned with the inability of many, many graduating high school seniors (and even graduating college seniors!) to write a coherent, grammatically-correct sentence. When faced with this problem I will confess that I at times find it ridiculous to even worry about the science issue, there are so many more, fundamental issues to deal with first.You have to find your feet before you can walk.

That said, my personal belief is that, even more important than increasing the knowledge base of science, we must increase the awareness of science. The distinction may be slight but it is important. Science has been a successful and productive means of advancing understanding not because of what it says but because of what it does.

Science is a method, rooted in historical philosophy that essentially provides a highly effective framework of how to approach questions. I firmly believe that, as with many things in life, the ability to apply a skill is more important than the ability to memorize the consequent results. If we provide the students with the tools to think objectively and analytically, then really they can derive the rest themselves, and, more importantly, they will be able to adjust to new situations, new questions, to find an appropriate answer themselves.

To me, this is the basic shortcoming I think of when people lament the lack of "scientific understanding". I'm not necessarily concerned that a person doesn't know the Mesozoic from the Paleozoic, or how an electromagnet uses electricity to produce a magnetic field, or what a gene transcription factor is. What I am very concerned about is gullibility. To me the lack of scientific education is most glaring not when a consumer fails to recognize a slight factual error, but when he or she reads a statement like "This formula releases a special form of mitochondrial energy that invigorates the cells" and fails to question what that really means, or if it's really even legitimately meaningful. This is especially true in the modern internet era.

Today nearly any fact can be obtained, any question answered from your home computer in mere seconds. "Fact acquisition" is not a problem; facts are abundant, and readily available. Education, in a sense, is at any person's fingertips, they merely have to look. The real challenge, the important skill, is the ability to discern which information is plausible and reliable, and which is not. Today, supposed "facts" are actually all too abundant and readily accessible!

I while back while lecturing to one of my classes I misspoke. It was a simple error, just the substitution of an unintended word for the intended one, but it changed the meaning significantly. I didn't even notice until I was preparing the next class, and had a recollection that wait, I might have said that wrong. In the next class section I asked to see a student's notes, and sure enough, there was the error. I asked the class why nobody had questioned what I had said, after all, taken at face value the statement had nearly perfectly contradicted the statement I had made immediately preceding the erroneous one. The half-joking response was also somewhat telling: "Well, because you're the instructor, we figured it must have been right!" This response would be warranted had I made a factual error in my discourse, after all, the students should not question every fact I submit, and are not expected to know the facts I am teaching beforehand, to know or recognize which ones I might have wrong. But the error I had made was not a factual one, it was a logical one: I had posed two directly competing statements and presented each as correct, when clearly they could both be true. The fact that no student in the class objected to this is exactly the lack of science education that I lament-- the ability to take knowledge and think about what it means, rather than just regurgitating the information (which any computer can do far better), and to apply the knowledge in a meaningful way.

I think that the national standards published by the National Research Council:
National Research Council
or the Benchmarks for Science Literacy published by AAAS:
Benchmarks for Science Literacy
give excellent guidance on what skills and concepts to teach. NSTA's Pathways to the Science Standards has excellent examples for teaching the concepts.

To answer your larger question, I believe that there need not be any conflict between teaching science and teaching other subjects. After all, students have to write about something, do their math with some numbers, and learn the history and cultural significance of something. Why not make science the core of a class curriculum? For example, let's say a class was to study a food plant such as corn. They could learn about plant growth and metabolism by doing a few safe, easy, cheap experiments. They could analyze their data using math skills. They could then communicate their findings with presentations, writing, graphs, or other media. They could study the role of corn in ancient American cultures, learning about history and religions. They could read literature that deals with agriculture or mythology of corn. They could study current events and economics as they interact with corn as a commodity. They could study climate and weather patterns that influence corn crops and economics. I'm just getting started.

But let's say that you're already doing your best to improve science teaching in the lower grades and just want some advice on teaching kids with sketchy science backgrounds. In my opinion, it's best to explore a few basic, central concepts thoroughly than to try to teach everything quickly. My candidates for central concepts of biology would be the following:
The first and second laws of thermodynamics: Nothing comes from nothing. Nothing disappears. Things can only change, not appear or disappear. When energy is changed, some is always lost. Matter and energy should be thought of as different things unless you're doing fission or fusion science.
Basic metabolism: Plants use energy from the sun to turn carbon dioxide and water into sugar and oxygen. When there's no sun, they do the opposite and harvest the energy. Animals need oxygen to break sugar down to release energy, water and carbon dioxide. Plants get most of their mass "from the air.
Basic genetics:Genes provide instructions for making living things, but the environment influences how the product (organism) turns out. Things acquired during life do not get passed on in the genes. The need for a trait does not lead to genes for the trait. Mutation is random.
Basic evolution:Individuals with more successful traits are more likely to pass their genes on. This leads to changes in populations and species (but natural selection and evolution do not act 'for the good of the species'). The species we see now are the result of natural selection, extinction and speciation (new species arising) in the past. What's good in one environment may be bad in another environment. "Fitness" means leaving more offspring.
Basic cell theory:All living things are made of cells. Cells divide to reproduce.
Basic ecology Matter (such as nutrients) is conserved as it moves through communities, energy is dissipated. Living and non-living things interact in many ways.

I think the CA standards are useful. But you raise an interesting problem, if the kids don't know most of the stuff from previous grades [except probably a few, who are therefore bored?].

James Trefil is a physics professor in VA who has been heavily involved with your question. My brother and a colleague team-taught a science course at the 'remedial college' level based on some book about the science everyone should know. My brother writes the following about the book and your question:
It was a trade paperback, 1991 (!), by Robert M. Hazen and James Trefil. All text, no equations, no review stuff at the end of the chapter, no illustrations to speak of. I don't know that they did any revised editions. They, I believe it's "they," also wrote a more conventional hardcover text with equations, problems, review questions, etc., on 'all of science.' I wonder how Bill Bryson's 'History of Everything' (?) would be as a text. Ann read it and loved it. I didn't like an excerpt I read of Bryson's Appalachian Trail book, nor was interested in any more science survey books, so haven't looked at it. JG.

I'm glad there are teachers asking questions like this one, even though it's unfortunate that they have to. Here's my list, with some brief explanations.

I'm a biologist, so my emphasis is on that field. I hope you get some answers from people in other fields, too!

Basics and the scientific method: *Learning to think critically, to be truly objective, and to be your own harshest skeptic, is more important than memorizing a lot of facts.
* In some scientific fields, things can be proved, and those fields tend to have laws (like physics). In some fields, very few things can be proved, so those fields tend to have theories (like biology). The lesson for students is that this should not be taken to mean that biological theories are controversial or unlikely to be true. Rather, since there's no way to prove certain things beyond any shadow of doubt, it's only honest to call them theories.

(This concept is not unique to biology--it is theorized, for example, that the continents were once all one, there is abundant evidence to support that theory, and no serious scientist doubts that theory. It cannot be definitively proven, however, so it is a theory, not a law.)
* Correlation is not causation! Here's a great example: Good dental health correlates with increased TV watching. A bad (or dishonest) interpretation of this observation could be that watching TV is good for one's teeth. More likely, people with enough money to buy TVs (e.g. most Americans) are also able to afford better dental care.

* The scientific method involves making a hypothesis based on observations, figuring out a way to test that hypothesis, and then critically examining the results of the test to decide if they're really telling you what you think they're telling you. Before any scientist's research is presented to the public, it is critically reviewed by other scientists (i.e. "peer review").

Biology:*Evolution. The concept that species, not individual organisms, evolve. "Survival of the fittest," then, does not refer to an individual organism staying alive, and it has nothing to do with being strong or fast or physically fit. It refers to the ability of an entire species to adapt to whatever conditions it finds in its environment. In evolution, the only thing that matters--truly the only thing--is reproduction. Eating or avoiding predators only matter if those things give an organism the opportunity to reproduce. Once an organism is done reproducing, its life is irrelevant (as far as evolution is concerned). If an organism cannot reproduce, its survival is likewise irrelevant.

* The concept of symbiosis: lichens are associations between bacterial symbionts and their fungal host, many corals have cyanobacteria in their bodies that photosynthesize for them, almost all plants have mycorhyzal fungi associated with their roots (and may not be able to live without them), there are more bacterial cells in the human gut than there are human cells in the human body,etc. Even the mitochondria in eukaryotic cells were once symbiotic bacteria. We will probably discover one day that symbiosis is the norm, not the exception.

* Ecology and ecosystem dynamics, including the concept that ecosystems are vastly complicated and all their components are in a delicate balance with each other. Changing or removing one seemingly insignificant component of an ecosystem can cause massive disruptions in many or all other components. Such changes are especially dangerous since we don't fully understand our ecosystems yet, and so cannot predict the results of changes we make.

*Similarities and differences between plants, fungi, animals, and bacteria.(Including interesting facts, like noting that fungi have more in common with animals than plants, and interesting exceptions where science isn't sure exactly what some organisms really are.)

*Basics of biochemistry: photosynthesis, respiration, and other metabolic functions.

* Overview of cell structure, function, and diversity.* The structure and function of DNA, and some ways people manipulate DNA in biotechnology and medicine.

* Animal and human anatomy and physiology, including lifestyle choices that affect our health.

Chemistry:*The unique properties of water molecules, and the absolute dependence of all life on this "universal solvent," its polarity, and its hydrogen bonds.

* Overview of the structure of matter, from sub-atomic particles through atoms to molecules.

* Characteristics of different kinds of chemical bonds.* Hydrophobicity vs. hydrophilicity (why oil and water don't mix, and how cells use their membranes).

Fundamentally, the most important thing you need to teach about science is that it is an active process connecting testable models (called theories) to practical experiment. Thus science does not address the 'truth' in a direct way. Instead it provides better and better models which must stand up to experimental test.

This is a somewhat conservative viewpoint as it places many kinds of study out of science, but would be supported by many scientists. For example, a field which uses current scientific results but for which predictive experiments cannot be made would not qualify -- cosmology until very recently, many area of social science in which experiments would be illegal or immoral,creation 'science' (which has a theory, but does not make predictions,it tries to justify theories by ad hoc experiments), and certain areas of theoretical physics, in which no known measurement scheme could be applied.

Note, I am not trying to denigrate theses studies in any way --they simply fail to meet the above definition. It is also important to note that science as defined above cannot itself be validated or proven. Effectively, the 'validation' of science is its application (for example engineering).

If the above definition is applied ruthlessly, many kinds of pseudo-science can be discounted as scientifically 'valid'. It goes without saying, however, that humans do science and it is a genuine human endeavor. The other point that is often missed in trying to teach science is that the practice of doing science often challenges the imagination and well as the intellect. In short -- most scientists do it for fun.

When I was in 6th grade, we had a programmed sequence of experiments involving candles, water and jars which lead the students(myself included) down the cherry path -- until a single experiment violated the whole assumed, but ad hoc development. Then subsequent (much more careful) work pointed out the error in reasoning and lead to a much more consistent theory. (you lit a candle in a water bath, put ajar over it and tried to predict how high the water would rise before the candle went out..) I learned a lot from this -- not facts, but principles which have stood me well since then.

I would not contest the need to teach some basic areas of science to students, but they should also get a rather thorough introduction into what a science actually is... too often the idea is lots in the deluge of 'facts'.