[sdiy] OT:5 IC design

[joe mc cool]

Please,

I am sorry to trouble you guys with this:

I am struggling to teach a course on Electronic Circuit Manufacture.  I 
need a design (any application) that features 5 IC's.

The build instructions and testing routines need to be idiot proof, 
suitable for youngsters, spelt out crystal clear.  I will put it 
together firstly on bread board and then on ferro board.  The components 
must be readily availble (RS).

Any pointers ?

Thanks a lot.

Joe