You'll need to delete that 2106 and then re-enter as Teacher Expense. First:
In the top menu, click My Account, then
Tools, then
Delete a Form (within Other Helpful Links)
Select Delete next to the relevant form (anything with 2106 in the description). Then go to:
Federal Taxes,
Deductions and Credits
Scroll down to Employment Expenses
Start Teacher (Educator) Expenses
