Put off your family vacation to help put some food on another family's table. About a year and a half ago, the San Francisco Food Bank, which moves 33 million pounds of food through its warehouse each week, started letting parents bring kids as young as 4 on Sundays to volunteer and help pack food for the needy. The program has welcomed families to sort produce, divvy up rice into individual bags, and stamp labels on cans. Regular three-hour shifts have been reduced to 90 minutes to accommodate the younger crowd, with about 80 to 120 people showing up each week. With the Food Bank receiving 25 percent more requests for food in March 2009 compared with the year before, every little helping hand counts. A Sunday at the Food Bank is no trip to Disneyland, but in these tough times, maybe that's a good thing.