Engagement entails much more than rote repetition of a procedure. Math worksheets tend to present very similar problem types over and over, leading to mundane practice of disassociated skills. For students who understand the material and successfully complete an assignment, another worksheet becomes meaningless. On the other hand, for the students who don't understand the material, an alternative method of instruction is what's needed. Another worksheet simply adds to the student's frustration, or worse, contributes to a belief that "I'll never understand math." A cute image or a "fill_in_the_blanks" riddle does nothing to increase engagement or learning (and let's face it, those riddles are not funny!). Instead, teachers need to increase engagement by providing students with exercises in which they discover patterns and relationships, solve problems, or think creatively about math relationships.
Multiplication worksheets are a quick and easy way to introduce some math revision at home. At first your kids may not appreciate being given extra "homework", but the advantages they will gain from "sharpening the saw" and practicing their math will serve them well; both back in the classroom and on in to later life. With a basic knowledge of Microsoft Excel or Word you can easily make your own math worksheets, but not everyone has that knowledge so it's fortunate that there are many websites dedicated to providing free printable resources, usually in PDF format. You just download, and print _ the only software required is the free Adobe PDF reader.