She needs to figure out her interests to get a sense of what she might want to do. If she wants to take the economics degree and general office work background to go back and get an accounting certification and a CPA, there are definitely straightforward avenues for a career to develop out of that both flexible and more traditional corporate jobs.
She can also recognize that she spent the last 10 years managing household logistics, keeping things organized, planning and anticipating future needs, coordinating competing priorities, budgeting expenses and and getting projects accomplished on time and under budget. Those are all skills local non-profits would look for in staff positions. She could start by reaching out to any of the non-profits that interest her see if there are any open positions available, she'd be able to take on a part-time no benefits position it sounds like. If she doesn't see any openings, she should still reach out directly and volunteer her time. Let them know she's looking to get back into the workforce after staying home to raise her kids, but she's interested in their cause and happy to do some volunteer work to start building her resume back up. My guess is she's probably got her stuff together with having 4 kids to manage so whoever takes a chance on her will find a way to utilize her skills.
She's just got to put herself out there and not worry too much about rejection or just silence.