Thanks for the suggestions! We did Greenwich, cable car and clipper last summer with some visitors from overseas. I wouldn't mind going again and booking for the planetarium at Greenwich but it was quite a lot outside and walking and I think it's a bit cold! We've never been to the IMAX at the science museum and I've just found a half price offer so that's our current freezing day plan, if the weather is not too bad might venture further afield and do some more travelling round London. Afternoon tea for children is brilliant! Dd doesn't much like cake though so only downside is I might have to eat her share
Or you could do the cable car one way like this: Get DLR from Bank or Tower Hill to Excel - this is an adventure in itself and is great fun. Cable car one way to O2 - it's about £3.50 with an Oyster card. Check out O2 - morning tea. Get River Clippers to wherever you want - Greenwich, or Embankment or Westminster? Finish up with a stroll along South Bank - get lunch somewhere, pop into Tate Modern, see what free concerts are on at South Bank Centre etc.
If you've already enjoyed that have you been on the Cable car across Thames to the O2? It's awesome and would combine well with a boat trip (Clipper's aren't expensive) and riverside lunch somewhere? Cable car is about £7 return on an Oyster card. I think the dc were free.
I have a rare day where I have my nearly 6 year old and not her toddler sister! I'd love to take her on a day out - for something we wouldn't do with her sister. We like going to the theatre together and she is quite girly. We are commuter distance north of London, so could go into town or herts/beds/cambs/bucks - don't mind driving a bit. I have been looking for a matinee theatre performance but there's no matinees of suitable performances on a friday.
I also want to take advantage of the fact it's an inset day and go somewhere that would normally be very busy at weekends/weekdays. We have done most of the major london sights/museums. also something not too expensive or which I can use tesco vouchers for!