As it is said – digital clock with large screen is a great way to teach child read the clock. This clock is built on ATmega168 microcontroller that is this might seem and ordinary digital clock but there is one odd – it uses no RTC timer chip but internal timer that is being triggered via external crystal of 32.678kHz. So this allows generating exact 1sec intervals while AVR is running with internal system clock at 8MHz.
Clock is equipped with two buttons that are led with audio tick and of course 32×8 LED display which gets data via SPI-like protocol (3 pins). And of course this clock was designed for kid – so it is enclosed in LEGO construction. Learning time can be fun.