Along with tomatoes, summer squashes strike me as the classic home garden plant. Hybrid zucchini varieties take up relatively little space and produce a volume of fruit that is legendary. We use most of ours to make zucchini relish, but breads and muffins make an appearance as well. And I suppose you can cook and eat the things too.
Direct sow outside when soil warms in hills three feet apart, three plants per hill (plant more seeds and thin to the strongest seedlings if you can). Squash need heavy feeding, and weeding while the seedlings are small. Leaving large fruits on the vines can inhibit the production of new ones, which can be either a negative or a positive depending on the circumstances!