The afternoon ratings do seem to be very low this week - but it is half term, so i'm wondering if that's effected it? CBBC have decided to premier two of their new shows All Over The Place USA and The Sparticle Mystery in the mornings, so maybe they know ratings are strong at that time during holidays.
Most of the afternoon ratings are going to be lower than usual - so yes the fact it's half-term may have affected it. Some ratings are decent - take the documentary My Life
on Tuesday, and of course last week when some of the UK were also on half-term The Dumping Ground still pulled in a respectable figure of 428k, though it will timeshift well.
They decided to premiere the two new shows because they feel there's a larger young audience available. 200k at 7:45am is pretty respectable, as is it in a 10:10am slot. However, it's also likely that on a school day, before kids go to school they would usually check to see what the CBBC/Cbeebies/kids channels have on offer, so early morning ratings may be as high or higher on a school day.