Dongdaemun Market hosts streets full of shops that specialise in certain products and we came across the toys and stationary stores just north of Dasangyo Bridge.
After our trips to Taipei and Tokyo and coming from six months in Hong Kong, I can't say that the stock sold in the Toys and Stationary streets of Dongdaemun Market were anything special (sorry - maybe to Korean kids, they are..).
Though brightly coloured and fun, much of the toys were pretty basic. Some brands such as Lego and Gundam did make an appearance, though more interesting were party-based items and craft goods.
Stationary supplies were strictly utilitarian and I didn't find anything with a unique appeal as I did in either Tokyo or Taipei.
In February 2009, Mark and Linh moved from the UK to the Far East to spend 16 months living in Hong Kong and traveling around East Asia. This website documents their journey.