Outdoor led wall panel - reacting when hit by a ball
My guess is that if you can't find something pre-made (which would be by far cheapest thanks to the efficiencies of mass production), the best way would be to have two panels:


The back panel would be an LED panel, protected by the front panel from being hit by the ball.
The front panel would be a plastic (i.e.,transparent) panel with sensors - perhaps in the corners - to detect hits.
Then you need a small computer (Arduino, Raspberry Pi, etc.) to connect it all together to change the lights as needed, keep track of the score, etc. The hardware shouldn't cost all that much, but there would be some significant programming involved. Not a trivial project, but a lot of fun if you are truly geeky (like me) and have time (which I don't :-( )