If worksheets had feelings they would be feeling pretty bad these days. It seems like every time I am in a professional development session about anything (math related or not) the professional developers take potshots at worksheets and teachers who assign them. Admittedly there are some pretty bad worksheets out there and I guess if your classroom revolves entirely around worksheets that might be a problem.
It is true that sometimes new technology like Khan Academy might be a better way to practice a skill but sometimes a well designed worksheet will also fit the bill. I like to create puzzle worksheets. I think good worksheets offer something you can't get from just doing problems in a textbook or on Khan. I try to make my worksheets interactive, engaging, and fun, while also offering practice with a topic. I also really love the Doodle Math Worksheets that Math Giraffe shares on her site and sells on Teachers Pay Teachers. This was going to be a post to introduce a new puzzle worksheet I just created for Factoring Trinomials but I will save that for the next entry. If you are curious you can find all of the puzzle worksheets I have created here.