Use Ontabswitch script trigger then in your script use Get(TriggerCurrentTabPanel) to get the current tab, then you would use if or case statement then perform desired steps or call another script.
sorry this is for fmp12 Im not sure about 10.
Since the OP is using FileMaker 10, those triggers are not available.
But the OnObjectModify trigger can be selected for a tab control and it will perform a script each time a different tab is selected. If you use the "Object Name" box on the Object Info palette to give each tab panel in the control an object name and then use GetLayoutObjectAttribute to determine which panel is now the front panel. You can look up this function in Help to learn the details.
Thanks a lot, PhilModJunk