I have been homeschooling for 5 years (three kids) and have a pretty good handle on things, except the one area where we are lacking is science. I've never been able to find a program I love and it's always just been kind of a hodgepodge.
The last few years we'd just do random unit studies - solar system, plants, whatever - and do a few activities, read a few books. This year I bought 'Christian Kids Explore Biology,' which is just okay. We are Christian but we aren't literal-6000-years-old-earth-humans-coexisted-with-dinosaurs-carbon-dating-is-nonsense type Christians when it comes to science. :) So a Biblical basis (God created the world) is fine, but this textbook goes a bit far sometimes. Also I am homeschooling a kindergartener, first grader, and fourth grader, and I'd like to use the same thing for everyone (of course adding more challenging work for the 4th grader - vocab, worksheets, whatever).
I am looking at getting a microscope and slides but that may have to wait til my summer purchases and go toward next year.
Our library has a small number of Magic School Bus DVDs but often, they will not play because they are old and scratched. The kids don't like them much anyway.
We try watching Bill Nye videos on youtube but most of them are such poor quality we can't stand to watch very long.
We do gardening big time, so they know all about plants, terminology, composting, worms, pollination, etc. We did a long unit on solar system last year and a long one on dinosaurs the year before. But I feel like it's not nearly enough.
I'd love to hear suggestions of what you use, especially if you are homeschooling multiple ages and using the same thing for everyone.
we love those book! you can read them as textbooks and do experiments or you can go off on side trails(thats what we do) with the books! we are in our second year of general science right now! but theres astonomy, zoology, solar system, biology, physics, chemistry, etc! i use them for all ages
I found Beakman's World on Netflix the other day. My 3rd grader enjoys watching documentaries on Netflix as well.
We use the Magic School Bus Young Scientist Club kits. I got a year membership for $120. They send a kit each month. It comes with experiments (some come with 4-5, some come with way more) and most of the supplies you need to do them. I supplement with library books, videos etc. because the kits definitely aren't meant to be a stand-alone curriculum. I like it because I don't have to round up all the supplies... I have a toddler and baby, I need things to be as simple as possible.
You might check out SuperCharged Science, Elemental Science, or Science Fusion. I've only used Elemental Science. It's all laid out for you, tells you what books to use with the Student Book and Teacher's Manual, has quizzes, very reasonably priced (like $35 for SB & TM), etc. I've heard really good things about SuperCharged Science. I think SCS is online.
If you're christian but not literal creationists, I would suggest Behold and See Science (from Catholic Heritage Curriculum).
At some point, as I'm sure you know, you're going to need a different program for the older child. Until middle school it's probably fine to group him in with his younger siblings, but he'll need more challenging material in itself eventually.
Have you thought about buying at your oldest's ability and then creating unit studies FROM THAT for your youngers?
ETA: check out Ellen McHenry's programs. We LOVE LOVE LOVE them and I don't see why they couldn't be used for multiple ages. It would be over the kindergartner's head, but the others would use it well I think.