http://www.topmarks.co.uk/Interactive.aspx#fmaths
A range of curriculum related topics categorized by developmental level. It gives an idea of how teaching with this technology would be appealing to children because of the use of sound and graphics. However some of the graphics correspond to Welsh social life and customs.

Interactive Whiteboard Resources
Another UK site with links sorted by year level and by literacy and numeracy.

The entire Crickwebsite  http://www.crickweb.co.uk/

Some great Game-based learning activities
http://www.ictgames.com/

Tips for Using Interactive Whiteboards
Ideas and Links to some free software

Links to Whiteboard Resources
Follow these links to find a range of resources

Birmingham Grid for Learning
A selection of downloadable resources to use with whiteboards

e-chalk
A UK site offering some free and some subscription-based resources to use with whiteboards

Stockton Teaching Resources
A selection of whiteboard resources (many can be used without a whiteboard) from the Stockton Local Teaching Area (UK)

Links Directory
To interactive whiteboard resources

SchoolZone resources
Download and use on your IWB. Over a thousand listed: search by keyword or browse by subject

iwb.org.uk
a rapidly growing bank of free to use tools and resources created for teachers who are teaching with an interactive whiteboard

Links on an Australian School Library website. These are generic links to good primary sites
http://www.sac.sa.edu.au/Library/Library/Primary/interactive.html

Summary site for interactive lessons 
http://www.fsdb.k12.fl.us/rmc/tutorials/whiteboards.html#sites

More free downloads- Scottish site
http://www.fife-education.org.uk/ict_in_education/SmartBoard/Downloads_NBfiles.htm

very useful
http://home.comcast.net/~dmharris5118/whiteboard%20site.htm

Australian based lessons
http://www.interactivewhiteboard.net.au/lesson.asp 

Summary site
http://www.amphi.com/departments/technology/whiteboard/lessonplans.html 

Outstanding summary site for IWB (some out of date)
http://www.teachers.ash.org.au/suel/white/white.html 

useful wiki space
http://teaching-with-technology.wikispaces.com/iwb 

Excellent new on-line collaborative tools free to schools
http://www.intel.com/education/tools/index.htm 

Try out an IWB blog site
http://www.whiteboardblog.co.uk/labels/IWB.html 

Tony Poultney’s vast Primary Toolbox Collection at
http://www.btinternet.com/~tony.poulter/

Woodlands Junior School – in Kent, England - 
http://www.woodlands-junior.kent.sch.uk/teacher/index.html

Athena at - http://www.athena.bham.org.uk/old/TeacherResources.htm

British Broadcasting Commission (BBC) at http://www.bbc.co.uk/learning/ or http://www.bbc.co.uk/schools

The Next 5 are very Numeracy Specific

Ambleside Primary Numeracy Hour
Teaching tools, tests, games and much more...Try our own Interactive Activities &Teaching Tools (Several of these activities use state of the art Internet technologies - (FLASH 5 plugin required)

http://www.ictgames.com/index.html
These games are generally targeted at infant school teachers and parents of infant age children.  

http://www.sac.sa.edu.au/Library/Library/Primary/maths/maths.htm 
This is a library site listing a lot of links to resources

http://www.teacherlink.org/content/math/interactive/flash/home.html
These are flash lessons and run from K-12 so hunt for the ones that are appropriate to primary (elementary)

http://www.teachingideas.co.uk/ict/iwbtips.htm
Select the Maths button to get the activities especially for Mathematics.

The following have great collections of free resources for teachers: (many of these would be great on an IWB)

Naturally some of these will link to each other but they could prove a useful place for you to start looking!