Duplo is great. The blocks are mostly big, so they cannot be swallowed. You can literally stomp on a block with all your power and it will not break. You have regular blocks but also trains, rails, wheels etc.

* My youngest at 6 months was happy for ~10 minutes just holding a red 4 x 2 block

* Now he's 10 months old and licks the blocks and bangs them together

* My oldest at 1 - 1.5 years old, tried to stack a few blocks together

* At 2 years old he was building large towers, to collapse them

* At 3 years old, I could build something for him and he could "help" and add stuff to the building (with fantasy running wild; stack 20 random blocks on top of a carwash I intricately crafted and that was so "planes could land to be washed")

* At 4 years old, he could build stuff by himself

* Now at 4.5 he's learning himself how to reinforce structures, how to build "bridges", build cars etc.

I have purchased Duplo for three friend’s kid’s first birthday and they have been a hit. Recommended age is 18 months, but 6 months to a year out, they get more use out of my gift than the others. Duplo is also compatible with Lego, which means they can be used as filler, etc. as they get older. Now one couple is having their second kid and I need to find a new present!

Search for 'duplo marble run'. I've found knockoff versions on ebay for ~$5. My 8 & 10 year old still love to play with the set. It's fun to build and fun to send the marbles down the path.

> realize that your child may not be interested in anything you are interested in, its ok.

I've been trying to get my son into STEM (robots, arduino, raspberry pis, everywhere). Alas, he is an artist and enjoys drawing manga, writing stories, and playing guitar. At first I was concerned because none of these are useful employment skills. I've learned to just go with the flow.