Even though I create educational resources, I also use some that are already out there on the market.  Here are a few of my all-time favorite resources.  These are items I have actually used and deem to be superior enough to merit my recommendation.  (Not many products make it onto my recommendation list.)  (And I don't get any kickback for recommending them.)  

Lapbooking:

Here is a very comprehensive site that covers not only how to do lapbooks but many free printables and other resources as well.  (Some of my things are listed in their resources.)   www.squidoo.com/lapbooking

General science resources:

TOPS Learning Systems:   www.topscience.org     

If you are looking for experimental science resources, you'll want to check out TOPS.  This is the height of high-quality, hands-on science on a shoe-string budget.  Fantastic stuff.  Only drawback is that they don't come with text, just experiments.

Extra chemistry resources: 

The Chemical Elements: a user-friendly history book about the discovery of the chemical elements.  Imported from England.  Charming narrative telling about the people who discovered chemistry and how they did it.  Published in the UK and available in the US through Parkwest Publications at parkwestpubs.com.  (When you get to the site you may need to click on "Tarquin Books.")   NOTE:  This book is on backorder until spring 2010.

Math:

"The Skip Count Kid"  skipcountkid.com      Math songs to help you learn to "skip count." There is a song for each type of "skip counting" (by 2's, by 3's, by 4's, etc.).  The songs are very catchy and singable.  I don't like educational songs that aren't singable. If I don't have the song humming in my head after listening a few times, it's pointless.  These songs are very well done and you'll find yourself singing them at odd times during the day-- which is exactly what is supposed to happen.  One of my children is an audio learner, and this tape was a life-saver for her when trying to learn the times tables.  I highly recommend it.   

History/Economics:

For middle/high school age:   Richard Maybury has a whole series of books that explain economics and how it affects world history.  If you are like me and had a mediocre public education, you need to read his books!  I can't recommend them highly enough.  His most popular books are:  

Whatever Happened to Penny Candy?

Whatever Happened to Justice?

Ancient Rome and How it Affects You Today 

The Thousand Year War (about the Middle East crisis) 

If you can't find them on amazon.com, try his own publishing site: bluestockingpress.com 

Learning the Greek alphabet:

My homeschool co-op classes LOVED this exciting introduction to the Greek alphabet.  "The Greek Alphabet Code Cracker" from Classical Academic Press (classicalacademicpress.com)  You must use the Greek alphabet to solve the mystery of the stolen urn of Achilles.  Find out who the theif is then track him to his secret hiding place!  Really catches the interest of kids ages 8-12.