I am a teacher, both by training and by nature, and I'm always on the look out for good teaching materials and methods. The past two years, I was a science teacher at a small private school; it was classical with Charlotte Mason influences. Mason was an educator in the early 1900s who offered some counter-cultural ideas about how to educate children. I don't agree with all that she advocated, but a great deal of it is very good. I was prompted to write a post after reading Auntie Leila's post about teaching science at Like Mother, Like Daughter. I'm not disagreeing, but adding to.
Science is about observation. That's where science begins, as Auntie Leila stated. The ancients began by noticing what was around them: this shiny yellow stuff is soft, but beautiful and shiny and doesn't rust like this other stuff here, lets call it gold. We can call the stuff that rusts iron. But then, they are much alike in their feel and quite different from the cloth I wear.
Science begins with noticing what is the same and what is different, and continues with classifying the things you see. The ancients classified different things by what they were made of... earth, fire, water or air. Aristotle refined these ideas with simple bodies and the elements and created a system of how they interacted. Other ancient philosophers had some different ideas. As time progressed and future scientists built from the bits that older scientists figured out, science progressed. Mistakes were made, wrong ideas decided on and then challenged and truth sought out (notice that this truth has a lower case "t").
The vast majority of science is about classification and identification, whether physics** (what is this that causes everything to fall to the ground) or chemistry (what is this that makes the vinegar bubble) or biology (what animal is this). After classification and identification comes questions of "why" and "how". These are questions you and a child can answer together. As you look at things, come up with a list of questions you can ask.
For example, you (generic you) know that everyone puts up Purple Martin houses in early spring and take them down in late fall. Why not leave them up all year? Why do they need a "house" and not just a single nesting box? What do Purple Martins eat? How big are their babies when they are born?
These questions will hopefully lead you in your quest to discover about Purple Martins, perhaps taking you to some place that raises birds, or cares for birds before releasing or some such. But, by learning to create these questions, you have become a scientist. Answering the questions makes you a bona fide scientist.
You can embellish on this process as much or as little as you like. You can write a paragraph, draw a picture, create a bulletin board, build a paper mache bird, build a Martin house, build a website dedicated to Purple Martin information or any number of projects that reflect what you've learned (kids seem to love showing off what they know anyways).
This is only the beginning, but this beginning will take you, easily, through 6th grade science. The embellishment gets more complicated and involved as the child gets older, but its still the same basic thing.
I love books, and so have some to suggest to help you on this endeavor:
Noeo Science Curriculum -- If you are feeling lost and want something concrete that tells you what to do, this site does it. I like the curriculum and made use of it teaching 4th grade (Physics II), 5th grade (Chemistry II) and 6th grade (Biology II) at the school I taught at the past two years. They have it nicely laid out, with curriculum guides, science kits and the books. You can get everything individually, too, which is nice. The following books are all from this set of curriculum, and these are the books I'm familiar with and taught with.
Usborne Science Encyclopedia -- I LOVE this book. Its full of colorful pictures and tons of information. Its overwhelming, so I hear, if you don't 'speak science', but I believe that can be overcome by patiently reading each page with a tiny bit of interest. Feeling lost? Learn along side your kids, and if you don't know an answer, say so, and look it up together. This book has sections for biology, chemistry, and physics.
Usborne Mysteries and Marvels of Science -- This book is focused on the details and side quests of chemistry and physics. Again, colorful pictures (I love books with pictures) and tons of information. My 5th graders learning about quarks and gluons from this book (the bits inside the bits that make up an atom).
I hope this helps some one figure out what to do for science, because science is the most awesome of possible subjects.
**A famous physicist (whose name I don't know) said "There's physics. All the rest is stamp collecting." He points quite directly the overwhelming aspect of identification and classification in much of "science".