Side yards are primarily used to get from the front yard to the backyard. They have a tendency to be long, boring spaces without much landscaping beyond ground cover and perhaps a few shrubs up against the house. Privacy can be a problem because they're so close to the neighboring homes. Stop wasting your side yard, and turn it into valuable garden space.
If the side yard is on the west or south side of the house, it most likely will receive enough sun to plant an herb garden. Many herbs, like basil, oregano, rosemary and parsley, originated in the Mediterranean so they don't need rich soil and can deal with a bit of dryness. Have watering source nearby, just in case. If the soil has been compacted from years of traffic traipsing through the side yard, plant the herb garden in containers.
Set up storage and a potting shed in the side yard and out of the backyard. It's out of view from the majority of both the front and backyards but still accessible. Landscape the potting shed with vines to cover it and shrubs on the sides. Place flagstones in front of the shed to create an entryway. Put two topiary rose bushes on either side of the entryway. Continue the flagstone path to the both the yards so it's easy to push a wheelbarrow full of soil or plants from the shed.
A side yard may be tiny, but there's always room for a child's garden. It's a good way to help kids learn about gardening and give them the responsibility for their own patch of yard. Easy vegetables to grow with seeds big enough for small hands to handle are squash, beans and corn. Fast sprouting and growing flowers include marigolds, zinnias and sunflowers.
Grow up rather than out when landscaping a narrow side yard. Hang planters from the wall of the house. Ivy geranium, sweet potato vines and begonias take to semi-shaded areas. Petunias, bacopa and nasturtiums grow well in the sun. Grow vines, like honeysuckle, up fences between properties. If there aren't any fences, grow climbing plants up a trellis. Stick with plants that grow tall rather than bushy. Snapdragons are a good choice, so is foxglove. Let some of the plants meander into the pathway rather than stay trimmed back. Curved lines break up a long, narrow space.