i have been on channel 4's what's this channel 4 (www.channel4.com/wtc4 then click on flash site and then click on history and then click on channel 4 timeline) and they have not put itv schools on channel 4 in 1987. they should have put it on there it was channel 4's first schools service.
well technically it was ITV's school service I suspect.
ITV's schools service was moved to C4 in 1987 after all transmitters were modified to carry C4. Remember up until 1993 C4 was effectively "ITV-2 ".
ITV were anxious to launch morning Daytime TV, so the IBA agreed to let them move Schools programming to C4 (but only after the last relay station in the UK had been converted to carry C4, this work was completed (by the IBA ) in 87.)
Yes, you have to remember that "ITV Schools" on 4 was controlled entirely by ITV in terms of editorial content, funding, etc. Channel 4 Broadcasting were simply given the job of handling playout and transmission.
In all other respects it wasn't in any way a Channel 4 service, programme strand or whatever else you may wish to call it.
The idents had a 4 logo on it purely as a station identifier - i.e. to clarify what physical channel was actually carrying ITV Schools' signals. 4 What It's Worth, Central could have kept the job of originating the output, and passing it to C4 for them to transmit on their transmitters, or the regional ITV stations could all have taken Central's feed and opted out of C4 altogether to transmit directly on the C4 network (as they always did with adverts).
But purely for reasons of technical ease, it made sense to let C4 handle the whole thing - purely from a technical standpoint.