Louisiana has taken steps to expand the foster care program, recently agreeing to pay for students to finish high school, rather than immediately cutting off aid when a child turns 18. Now, state officials want to find a way to care for foster children until they turn 21. Lawmakers had to come up with $1 million in the current budget year for the expansion that continues paying for foster children to reach high school graduation or age 21, whichever happens first. Financing for housing, food and other services for foster children through age 21 after they graduate would carry a larger price tag. State officials launched work Friday to design a program that would extend the foster care age, saying Louisiana should do more to care for its children.