chucktodd:
I thought the OP what trying to generate a competing product for peanuts.The design and software should not require much effort. If you have accurate spec's and a functioning master clock to validate your design, the actual clock should be easy. The tough part is the ergonomics. What will people accept, and how much will they pay for it. If you really wanted to throw a micky, add a dormant wifi port that kids could find. Change the display to a TFT so they could post 'Sam loves Niki!'.
Chuck.
p.s. you could really go great guns with this project. include the WiFi port (EPS8266), add a simple CCD camera behind the clock face, include a mic, call it the Homeland Security lockdown monitor System. Design the mic for gunshot triangulation. include a SMS module that can send text to the 911 center when students drop books on the floor. Report any loud outburts as violations of 'safe space' rules!
Shhh! You are giving my plans away!