Steve Wyborney recently published this article on Edutopia about a series of math problems he has created on Powerpoint called, “Splat!” The challenges begin at a low enough level that you could use them with Kindergarten, and increase in difficulty to a point that even secondary students will enjoy the intellectual stimulation. Steve provides all 50 of the downloadable Powerpoint files here, along with a video in which he explains the process. Basically, students are shown a group of dots, some of which are then covered with one or more “splats.” They have to deduce how many dots are under the splats.
I love the potential for rich math conversations with this activity and the natural algebraic thinking that will evolve from solving each of these challenges. Thanks to Steve for providing these great resources free to educators everywhere!