This sketch allows students to experiment with the parameters in standard and vertex forms of quadratic functions. After gaining some experience with those forms, there is a game to play.
Clicking target practice makes the graphs go away. Set the parameters to try and match the purple parabola. With which form do you have the most confidence?
When you're ready, try the game! Here's that applet: https://www.geogebra.org/m/VwAjXFNE