Here are some great websites to utilize when delving deeper into a topic.
Internet Safety
Common Sense Media
NetSmartzKids
Search Engines
Kiddle
KidsRex
General Reference
Your Dictionary
Encyclopedia
Thematic Pathfinders
Bibliography & Citing
Keyboarding & Mouse Skills
Typing Pal
Mousing Around
Reading & Phonics
Fast Phonics
Spelling City
Get Ready to Read
Starfall
Readquarium
Primera Escuela
Text Structure Practice
Math
NCTM - Illuminations
Shodor Interactivate
Nat'l Library of Virtual Manipulatives
Fact Power
Smarty Games
Math Playground
Math is Fun
Cool Math
Science
Exploring Nature Educational Resource
My First Garden
Space Websites
Arkive - wildlife films & videos
Kids Health
Chem4Kids
Earthquakes for Kids
Kids For A Clean Environment
Try Science
Animal Research
Social Studies
50 States
World Countries
National Geographic for Kids
Old Farmer's Almanac for Kids