Secretly, I have always loved worksheets.
At least math and logic ones. I treat them like puzzles or games, though.
DD1 has at various times been into word searches, crossword puzzles (she just liked filling in the boxes with letters), and workbooks. But she likes to choose which workbook pages to do, and she will tell me straight up if she doesn't like the directions. She refuses to trace numbers and letters (most of which she can write freehand), or do color by numbers, etc. I support her wholeheartedly - I really DON'T see the point of color by number, unless the kid is excited about what the finished product will look like if they follow the instructions. She says "I already know my colors and my numbers and I can tell it's a monkey, so why can't I color it any way I want?" LOL.
As for teaching kids stuff early, I guess it depends on what you mean by "teaching." I probably pointed out letters and numbers and colors to my kids when they were barely 1, not to get them "ahead of the curve" but just because I think learning is fun and part of everyday life. (A major reason why we are homeschooling them is to nurture that idea!) I have definitely done less of that with DD2, but somehow she still knows all the parts of her body as well as at least 8 or 9 colors. All without a worksheet.