Line of Learning

How do elementary students learn science? 
I believe elementary students typically learn science through hypothesizing, experimenting, recording data, and drawing conclusions; essentially, they learn science by being "walked through" the scientific process. At least, this is how science was taught in my elementary school. 
Of course, there is no one single way to teach science to a class of elementary students. Different methods work for different classrooms, and with science being a subject that can be daunting or scary to some students, individualized and differentiated learning is vitally important. There is no one-size-fits-all method to learning science, and I believe an effective teacher understands that and tries to facilitate learning through a variety of methods rather than just one stagnant method. 


What classroom environments facilitate elementary students’ science learning? 
This was somewhat addressed in the above response, but I will elaborate. Teachers are responsible for establishing a classroom environment that is conducive to learning at all levels. They are responsible for taking the "scary" out of science by creating collaborative, innovator-friendly classroom communities which focus on both the process of and the reflecting on science. True learning - and by this I mean learning conceptually, rather than mechanically - can only occur if both of those components are present in a classroom.
A classroom environment that encourages exploration in order to "discover" new concepts and ideas, an environment that provides ample opportunity to reflect and question and collaborate with others - this is the type of environment that facilitates learning. Science becomes less of an abstract concept when students are meaningfully engaged in activities rather than just being "walked through the process," and thereby becomes a dynamic, exciting and appropriately challenging subject. A classroom environment should encourage this kind of learning and thinking in order to effectively facilitate students' learning of science.


What should teachers know and be able to do to design and foster effective elementary science learning environments?
Teachers should know that effective learning does not come from a lecture or a slideshow, and that giving up some of the "control" is a simple part of teaching science to elementary school students. Teachers should be able to design a curriculum or environment (as aforementioned) that provides plenty of opportunities for exploration of ideas, an environment in which knowledge is shared between students as they learn and discover. These environments should be void of busywork or arbitrary worksheets that bear no conceptual significance.
Instead, they should open up spaces for children to truly gain an understanding of science. Yes, we know x+y=z, but do we know why that is true? And do we know how to prove it? These are the questions that need to be asked by both student and teacher in an elementary science classroom. And the teacher should understand that one wrong answer may not mean a student "doesn't get it" - they, too, should be asking why this may have happened. They facilitate an environment in which scientific thinking and the scientific process is natural and an integral part of the way the classroom operates, not just parts of a lab report waiting to be filled out at the last minute.
Essentially, a teacher should know how to foster effective elementary science learning environments by creating one that promotes thinking in the truest sense: learning, understanding, questioning, synthesizing, and reflecting. They should be able to create environments in which all students (eventually) feel comfortable going through that process on their own, not needing hand-holding or static lecturing along the way.