Some of my favorite alternatives to worksheets are board games, color-by-numbers activities, and task cards. Here are some examples that I have used recently.
Angle Addition Board Game: Directions and Questions I put out the directions and the cards and allow students to choose one childhood board game. Right now I have snakes and ladders, trouble, and candy land.
Area and Perimeter Task Cards Task Cards are a good way to have students work on challenging problems. I also use them often for word problems. Sometimes students can be thrown off by a long list of problems. The task cards just split the work into manageable chunks.