Apologia's "Exploring Creation Series" is the #1 science curriculum for homeschoolers! I think it is the very best way to teach a family all at once, since it covers ages K-6th grade. Instead of trying to do a "cover everything" approach, Apologia textbooks are very specific to one field of science, such as Botany, Zoology, Astronomy, etc. which is not what we are used to for young children, but oh, it works so well! We can really delve into the subject! One textbook is to be used as a year-long family unit study which I really appreciate, as it is so much easier to teach all the kids the same topic, and do the experiments together.
The chapters are fun to read aloud together, as the tone is conversational, like "let's all learn together!" There are hands-on activities, and experiments at the end of each chapter that we had a good time doing, plus they didn't use any odd ingredients so I could really pull them together quickly—I love that! Each student develops their own science notebook that contains their writing "narrations" of the things they have learned along with their illustrations, vocabulary words, projects, etc. This really works and is fun! My kids were excited about the cool science notebooks they were involved making.
One of the things I really love about Apologia science books is that I don't have to always be running interference, and trying to explain our faith in a God who created the universe. That seems to be a dominant problem when using secular science resources. When teaching astronomy, I am always faced with the Big Bang theory, the "trillions of years old" stuff, and trying to keep faith strong in the face of scientific "proof" that we are all evolved creatures living in an accidental universe. Apologia's Astronomy book is fabulous for giving reasons to support faith in God while teaching scientific truths! One of the interesting facts presented by this book is that Venus spins the opposite direction than the other planets in our solar system. The Big Bang theory says a big explosion set the planets all spinning, whirling out the same direction from a central "bang". If this was so, Venus should also be rotating the same direction. I love learning facts that support Christian doctrines!
These quality hardcover books are full of gorgeous full-color photos and pictures, interesting information. Opportunities for discussion and narration are inserted during the lesson. Experiments and assignments follow with opportunities to add to your notebook. Each book is divided into chapters that I use as our week's science focus. Written on a 4th grade level, so young ones will enjoy hearing it read aloud, and older students can read it themselves (although they still sure enjoy hearing it read aloud in a family setting, where discussions can develop). Information supports the National Standards of Science, but more importantly, supports Christian beliefs. This in-depth approach uses the elements of the Charlotte Mason and classical methods for a wonderful learning experience!
Choose the topic your family is most interested in learning first—that's the fun of it! Then progress to the next topic of interest. Here is the order they were written in, if you have no preference: Astronomy, Botany, Zoology 1: Flying Creatures, Zoology 2: Swimming Creatures and finally, Zoology 3: Land Animals and finally Human Body and Physiology. If you are wishing for more, no worries: two books, one on Anatomy and another covering Physics + Chemistry are in the works by this excellent author!