You can grow several vegetables from kitchen scraps. Here are some common ones:
Green Onions/Scallions: Place the root ends (about an inch) in a jar of water, and they will regrow new green shoots.
Lettuce: Place the bottom (core) of a head of lettuce in a shallow dish with a little water. New leaves will grow from the center.
Celery: Cut the base of a celery stalk (about 2 inches from the bottom) and place it in a shallow dish of water. New stalks will emerge from the center.
Carrots: Cut off the top (about an inch) and place it in a shallow dish with water. Carrot greens will grow from the top.
Bok Choy: Place the root end in a dish of water, and new leaves will grow from the center.
Potatoes: Cut a potato into chunks with at least two "eyes" each and plant them in soil. New potato plants will grow from these pieces.
Ginger: Plant a piece of ginger with a bud facing up in soil, and it will produce new ginger shoots.
Garlic: Plant individual garlic cloves with the pointed end facing up in soil, and they will develop into new garlic bulbs.
Onions: Plant the bottom (root end) of an onion in soil, and it will grow new onion shoots.
Tomatoes: Squeeze out the seeds from a ripe tomato, rinse them to remove the gel, and let them dry. Plant the seeds in soil, and new tomato plants will grow.
Peppers: Plant the seeds from a bell pepper or chili pepper in soil, and they will grow into new pepper plants.
Remember that while regrowing vegetables from scraps can be fun and rewarding, the new plants may not be exactly like the original ones you bought from the store. Also, some of these vegetables may take a bit of time and patience to grow fully, but it's a great way to reduce waste and experiment with gardening.