Leapin' LEDs II
Electronic
74HC00, 74HC76

Here's game to see how fast you are on the trigger (or at least the key!).

The object is to light LEDs 1 through 4 as quickly as you are able or with as few presses of S1 as you can.

To play, turn power ON. LED 1 lights.

Now press S1 until LED 2 lights. But, if you're not lucky, only LED 1 lights. Continue to try to get all the LEDs to light up (LED 1,2,3 and 4).

The secret of this game is to press S1 at exactly the right moment to light the LED. Timing's been an important part of all the digital circuits we've played with so far.