So, SD-card cameras are better than the really basic ones because they offer greater flexibility to the user.
Now for the awkward bit: 'Where can you get one for under �30?'
You
might be able to find one from an internet supplier but, by the time you've taken p&p into account it might still end up over �30. Additionally, you could end up with problems if the supplier e-mails you to say "Sorry, they're out of stock but we think we might have some more in time for Christmas".
My personal recommendation would be to forget the internet and look for a reputable make from a decent High Street supplier, even though this might take you a little over your budget. With that in mind, there doesn't seem to be any real choice. There is only one such camera which is widely available. It's the
Vivitar 3105S which is a few pence under �34 at either Tesco or Argos.
As I've stated, that camera is the only one which you can readily find around the �30 price mark. However, I should make it clear that (as I read the specification) it doesn't come supplied with an SD card. It's got a small amount of built-in memory, so it can be used 'as is', in the same way that the cheaper cameras can but it really needs an SD card added to it for best use.
I advise having a word with your daughter-in-law. It might be that she already uses an SD-card camera herself and has got one or two spare cards. In which case, there's probably no need for either you or your daughter-in-law to buy a card for your grandson's camera. However, if you do decide that one of you ought to buy a card for it, you should most definitely not buy from Argos! Their cheapest SD card is a 256Mb one for a whopping �24.99! You can buy one, with the same capacity, online for �5.95!
http://www.memory