classafloat.com 
ages 16-19 tuition-based.

Beastacademy.com
fun math item for Grades 2-5 that are problem-solving/challenge-based

Brave Writer

Brainquest.com 
educational trivia cards, workbooks & apps that are good family fun

homeschoolbuyersco-op.org/ 
Buyers club discounts on curriculum etc.

Khan Academy
Provides a free, world-class education to anyone, anywhere.

Math-U-See
DVD program that breaks down skills into doable lessons 

Mathworksheet.com
Make unlimited free printable worksheets

Mental Math
Mental Math in the Middle Grades and Mental Math for Junior High are good supplements

onlineG3.com
fee-based courses for junior high/high school students based on skill level not age.

Rainbow Resources
1-888-841-3456 has a wealth of creative ideas for working with your kids on almost every topic 

Studyladder.com
sequential learning on several topics including Spelling & Grammar - free & subscription levels available

Summit Academy
FREE accredited vocational training program in Mpls, MN.

The Thinking Tree Branch
A Branch an extension of the Thinking Tree 

Uncollege.org

Used Curriculum
used curriculum and more site