I'm going to convert part of our backyard into a veggie garden this fall.  It's an old dog run, so it's long and narrow.  I would love to do raised beds but I don't have the money to do so.  The area gets full sun at all times.  I am not really familar at all with vegetable gardening, as I've only had flower gardens before (and mostly containers at that).  What do you recommend I plant that is easy to take care of, will yield well and is hard to kill?  I really want to have my three and five year old help with the garden as much as they can.  I am looking for advice on what to plant, for both a fall/winter as well as a spring/summer garden.  I don't plan on doing raised beds, but if I can figure out how to I will.  Thanks for the replies!

Does your city have a department that helps people with this sort of thing?  I know Berkeley does.  Maybe you can talk to people at a gardening store. 

Find where your County Extension office is located. They should know some plants specific to your soil and location.

The easiest things I found was mustard greens, potatoes, zuchini, and tomato plants...provided they have well drained soil. Where they didn't grow good was heavy clay soil that turned to concrete when wet. 

Tomatoes adore sun and like heat, as long as they get enough water.  Lettuce is really hard to kill, and so are radishes, which are really nice for kids, as they sprout fairly quickly.  Beans and peas are also pretty hardy.

In addition to your County Extension Office, talk to a local nursery - the ones near me all give free advice (in the hopes you'll buy something) based on what you're interested in, where you live, and the amount of sun.  This late in the season you might want to get bedding plants.