What about remove some of the toys and then reintroduce them every now and again. My 2.2DD gets bored of her toys so I always have some older ones in the cupboard to pull out on those days. I find keeping them rotating really keeps her interested, even if only for a few hours.
Otherwise, have you found the ideas for entertaining toddlers thread? It has a host of ideas of things you can do with your toddler from other mums.
I try to make different games as much as possible, skittles with empty toilet rolls, posting photos or pics we have cut from magazines into and old tissue box, dress ups... and this week we discovered Clag! DD is loving pasting things onto paper !
I am sure you have a host of things you do with your DS, maybe just mix them up a bit so they all become fresh again.
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