Target sells these incredibly ugly, yet super functional plastic plates for 50 cents. They are huge, very lightweight, and have this rim around the edge that makes them surprisingly functional. Perfect for plating sandwiches, dumping out a bag of salad, washing and serving fruit like cherries and strawberries, cutting cheese, eating messy-ish foods like pasta with sauce, etc.
https://www.target.com/p/10-5-plastic-dinner-plate-room-essentials/-/A-80138159
they also sell these equally hideous "meal bowls" that are incredibly useful for like, microwaving oatmeal, storing fruit, mixing tuna salad, eating cold cereal and pasta, etc.
https://www.target.com/p/37oz-plastic-cereal-bowl-polypro-jet-gray-room-essentials-8482/-/A-85443068
For 50 cents a piece, they are cheaper, and sturdier, than disposable plates, although they eventually (after a few weeks of daily use) get a kind of yucky residue.