Below you will find many websites that have Language Arts content:
ABC Mouse
Vocabulary.com
Jumpstart
Room Recess
Scholastic
BrainPOP
Teach Your Monster
Storynory
Storyline Online
Phonics Games
ABCYA
Star Fall
A Book and A Hug
Roy the Zebra
Story Place
Turtle Diary
Splash Learn
Reading Eggs
Spelling City
EPIC!
Flocabulary
Arcademics
PBS Kids
Raz-Kids
Funbrain