As my son is always the first one of the family who wake up on weekends, he asked me to build him an alarm clock. As he can't read the time, he said that it should have a LED that signals with different color if it is okay to stand up or not.
As usual my daughter liked the idea also. She is bit older and can read the clock so she asked for a clock with display. And of cause it will be nice when it shows the outside temperature, so that she know what kind of cloths are okay for that day.
It is working with an ESP8266, OLED and WS2812 LED. The firmware makes a NTP request every hour to keep the time in sync.
Hope it is useful for some other dads. ;-)
See my progress and some more pictures on http://lazyzero.de/en/elektronik/esp8266/oled_clock/
Find firmware on github: https://github.com/lazyzero/ESP8266-Children-Alarm-Clock