For Math Dictionaries/Words Help:  (especially good for kids)

For Free Graph Paper (many types ... scroll down) Generator (in .pdf format):

For Grades K-8 General Mathematical Assistance:  (this one is fun !)  (K-8 Screen-Based Tech w/ Math)

Here's one resource I found from the last link:  (you need to create an account w/ username and password, [it costs ~$40/yr ; and you can evaluate it for 10 days free] but this is great!)

For Grades 9-College General Mathematical Assistance:

For Virtual Manipulatives:

For Factor Tree help:

For Penrose Tilings: (scroll down)

For Golden Pentagons/Pentagrams, see: