I read various threads but this is confusing. Am I understanding things correctly?

For one full day in London, we (1 adult + 1 teenager 13 yo) plan to buy two one-day travelcards (one at discounted child rate) at a National Raiway Station office. Travelcard is orange in color. There is a National Raiway Station office at Victoria station I think, which would be perfect. If not, where is the closest station?

I already printed vouchers for Tower of London, River Cruise, and Kensington Palace.

In addition to one full day, we have two half days to spend in London. For that, I think I should get Oyster PAYG for me. For the 13yo I don't know which is the best. I don't have enough time to order a photo Oyster for her.

Help me check please. Thx.

For my 2for1 cards, I used my two train tickets (not travelcards) that I had purchased at Gatwick. I had a ticket for going into London and one for leaving again.

I showed these tickets as proof of purchase when using the 2 for 1 cards.

I know we never used an Oyster card since we didn't want the hassle of topping or returning the cards.

Yes, there is a National Rail office at Victoria Stn.

If you use PAYG, the Oyster card wil not charge you more than the daily maximum tariff, that is the advantage of PAYG especially if you don't know how many times you will use the tube/bus during the day.

Not sure how to advice about the photo, sorry.

If there isn't time to get a photocard for your daughter, it looks as though you'll just have to pay adult rates for her. You could try playing the innocent with the ticket clerk when you go to get your Oyster cards.

Schuler -- if they're not coming into London by train, your good advice won't apply.

Patrick -- do they need a photo of the girl BEFORE arriving in London? Way back in the day, I just got a photo at one of those cheap portrait photo booths at Victoria (which may not be available anymore).

BigRuss: Those photos back in the day were for the old, pre-oyster travel cards.

Patrick and the OP are talking about photo id oyster card for discounted child fares. One has to get them in advance.

<<< For the 13yo I don't know which is the best. >>>

More one day child Travelcards - think they cost £2. You should be able to get thhem at the same time as you get the other Travelcards - just ensure they have the correct dates on them

Raindrop, pardon me for butting in, but I have yet another Travelcard/2 for 1 voucher question. One of the attractions that is listed as a 2 for 1 deal tells us that only a rail ticket in and out of London can be used -- not a 7-day paper pass for the Underground. How common is this?