Add option to add $$ to tuition as a donation toward a cause

Please add the option for a parent to add an amount to their monthly tuition as a donation toward an active fundraiser. For example, add $3 to their monthly tuition to go toward a fundraiser we have. This would pop up and ask if they wanted to add a specified amount to their tuition before finishing registration. They should be able to opt-out at any time like auto-pay. Thank you!