Learning English
LearnEnglish Kids has lots of free online games, songs, stories and activities for children to have fun and learn English too.
http://learnenglishkids.britishcouncil.org/en/

English Language Practice Activities
Young ESL students will find here lots of online activities and hundreds of printable worksheets that can help them with their English. The website is also a resource site for parents and teachers of young ESL learners. Free, ready-to-print teaching materials including flashcards, quizzes, games, song lyrics as well as a big collection of useful links to other ESL/EFL websites.
http://www.anglomaniacy.pl/index.html

e-Learning ESL
http://www.e-learningforkids.org/courses.html#englang

Online English Activities
Games and Worksheets to boost your Vocabulary, Spelling and Grammar
http://www.syvum.com/online/english.html

English 4 Kids
(Ignore ads and scroll down to green bar)
Printable ESL Worksheets, Games for ESL Classrooms, EFL Videos Tutorials, PPT Lessons, Interactive Vocabulary & Grammar Activities, Teaching Downloads.
http://english-4kids.com/

English Language Games
(from Fun with Vocabulary)
http://www.vocabulary.co.il/english-language-games/

Science
(plants and cycles)
http://www.bbc.co.uk/bitesize/ks2/science/living_things/