Hi tcliew80!
In case you bought your Little Math kit more than a year ago, please try uninstalling your Little Math COMPLETELY (during the uninstall process, choose to delete all data).
Once uninstalled, go to your ACCOUNT > Purchases > Little Math Software page to download and install the latest version of Little Math. For detailed instructions, please refer to this article:
Installing and Setting Up Your Little Math
http://support.brillkids.com/entries/20432326-installing-and-setting-up-your-little-math-from-your-brillkids-accountAfter installing the latest version of the program, you should be able to activate your license key successfully. Instructions for activating your key and downloading your lessons are also included in the article linked above.
I hope this helps!
In case you need further assistance, please email us at support @ brillkids.com.