Jill Biden is going back to her whiteboard. After months of teaching writing and English to community college students in boxes on a computer screen, the first lady resumes teaching in person Tuesday from a classroom at Northern Virginia Community College, where she has worked since 2009. She is the first first lady to leave the White House to log hours at a full-time job. “There are some things you just can’t replace, and I can’t wait to get back in the classroom,” she recently told Good Housekeeping magazine. The first lady has been anxious to see her students in person after more than a year of virtual teaching brought on by a pandemic that continues to challenge the Biden administration. A working first lady is a “big deal,” said Tammy Vigil, a Boston University communications professor who wrote a book about first ladies Michelle Obama and Melania Trump.