Welcome to Curious and Useful Math! Here you will find tricks and rules for quickly calculating certain types of math problems. There are also some entertaining trivia and math facts that are nice to slip into casual conversation.  I liked the Bible Numbers 

Snap Math - check the basic facts math game

Flash Card for Kids - Give yourself a tune-up.

Math Archives - almost all types of problems have drills at this site

Multiplication java applet to help you understand math game

Multiplication a concentration matching game, make your own games and drill sheets.

Multiplication Tips Knowing these makes it easy to do problems.

The Fractionator easy to use and understand

Math Tool
Math Goodies good explanations with visuals that really help

This site will create a worksheet to your specification...one of my favorites.  It's great for making worksheets to go over the problems your child needs more work.  The ultimate in individual education.

The program is called "Multiplication Flashcards" and is a great tool for the homeschool parent to use to help teach the child that is learning his/her multiplication tables. The interface is simple and geared for the very young child. The program can be controlled by using either a mouse or entirely by the keyboard; making it fully accessible to children with physical handicaps. Last year I sent the program out as an email attachment to over 250 home school families that requested it after I posted it on a homeschool discussion board. 

Here's a great site, courtesy of Santa Monica College. Click on the headings for any subject, and get sample problems, explanations, etc. - like a math course on a page! ~psam 

Complete math courses for free, just has lots of adds, but no pop ups that I could tell. Check out this site

The following worksheets can be loaded into your computer area by clicking on (Word 6 file). In the response box click on "Save file" and you will then be asked to specify which directory you want to save the file in. You can then print yourself a copy to work from.

Fractions, Equivalent Fractions and Decimals. GRADE LEVEL: 7-8

Dividing Simple Fractions 
Rule 14: To divide one fraction by a second fraction, convert the problem to multiplication and multiply the two fractions.

The following worksheets can be loaded into your computer area by clicking on (Word 6 file). In the response box click on "Save file" and you will then be asked to specify which directory you want to save the file in. You can then print yourself a copy to work from. 

Great education resources with graphs and other simple solutions to math difficulties for the teacher and the student.

The Math Forum, an online community funded in part by the National Science Foundation and hosted by Swarthmore College
The Math Dance is a site from a math author.  They have several chapter for free for education purposes only.  So please remember this and do not resell the pages you download and print. 
Math games including Hangman and other fun things.  When the drill and skill gets tiring, it's time for some math games!
Algebra for Six year olds is a homeschool site about introducing the basic concepts to your elementary kids.  Great links on the bottom to other math lessons.