Activity expenses

Legal agreements from 2008 obligated me to pay for a large fraction of medical and tuition expenses, but did not mention activity expenses. In 2009 I agreed to also pay for a large fraction of kids activity expenses.
My ex has filed a motion to force me to pay for a large fraction of the 2008 kids’ activity expenses that she incurred. She claims it was an oversight, and that these costs are part of child support from that period. I don’t agree.

In late 2009, the judge signed a final distribution order that settled all prior claims for alimony and equitable distribution.

Is her claim legitimate?

Unless the child support order required your contribution towards extracurricular activities you will not have to pay the past expenses.