BBC has games for Science, Maths and Literacy
http://www.bbc.co.uk/bitesize/ks1/
Woodlands Junior
http://www.primaryhomeworkhelp.co.uk/maths/
http://www.topmarks.co.uk/maths-games/5-7-years/counting
http://www.topmarks.co.uk/maths-games/5-7-years/ordering
http://www.topmarks.co.uk/maths-games/hit-the-button
http://www.ictgames.com/resources