Cut up all the vegetables; yellow squash, zucchini, and onions. Put them into the slow cooker including the corn.
In a medium saucepan, cook chopped tomatoes over medium heat and add ½ cup water. Cook tomatoes until mixture turns into a tomato sauce. Add tomato sauce to slow cooker.
In same pot (I like to keep the dirty pots and pans to a minimum) brown ground beef, drain and add to slow cooker.
Add other ½ cup of water, ketchup, brown sugar, vinegar, Worcestershire sauce, chili powder and flour to slow cooker.
Set cooker to low and cook for 6 hours. Serve with hamburger buns and enjoy.