Introducing the most exciting toy that you will make and then want to play with again and again and again. After all, it is not easy to roll your marble all the way to the collector tray, when there are 8 different levels of friction coefficients you have to conquer. Gravity and friction are fundamental concepts that a child experiences at an early stage. These concepts are also introduced as part of curriculum at primary level (through their application in concepts such as force, motion and energy). Slippery slopes friction slider stem, educational, construction, DIY toy demonstrates engages children in learning these concepts by demonstrating the effect and working of friction through its gameplay. When assembled, slippery slopes friction slider consists of 4 channels arranged one below another, to form a continuous track for a marble/ball to roll through from start to finish. These channels have bases which are covered with interchangeable material (with different friction coefficients). The objective is for you to guide a marble/ball from the start point to the collector at the base using gravity and controlling (using the handles, like a joystick) the inclination of the channels through the different levels. Each level offers a new and unexpected degree of challenge for the ball to roll (since friction coefficients of different surfaces such as foam, sandpaper, plastic, etc. offer different levels of resistance). The gameplay can be made even more challenging by adding further variable obstacles in the form of rubber bands (in slots provided). Everybody is a winner though, because crossing every level awards you some points. The highest points can be won by guiding the marble/ball through all 4 channels, from start to finish (collector basket at the base).