If you think a moving target is hard to hit, just wait until you try to hit a pair of blinking LEDs!
This project tests your ability to anticipate what an electronic circuit will do. To play, set the select switch up. LEDs 1 and 2 light and start to blink off and on very rapidly (it looks almost like one light moving from side to side). Your "rifle" is S1.
When you think the time is right, press S1. If you "fired" at the right moment, LED 1 goes out. Set the select switch down and press S1 again. If your "aim" is good, you'll "shoot out" LED 2. If you're a really good "shot", you might get LED 1 and 2 out with just one press of S1.
On the other hand, it might take several press of S1 just to get one of the LEDs to go out. Be sure to set the select switch down before trying to "shoot" LED 2. If you don't, you'll discover that ... (hold on, we shouldn't tell you everything. Try if for yourself and see what happens.)
When the both LEDs are off, press the S3 key.
This means the circuit stays at the start position and you are ready to start again.