As I've stated many times before, we are a K'nex family. My husband loves building with their sets. I swear he has just as much fun as the kids do! These next two sets are for the five and up bunch. Madison is six, and at times, she had to take breaks from creating these. However, she did enjoy it and kept asking to build the next one. There is lots of small pieces too, so if you have other small ones in the house, I recommend building these at their nap time.
Collect & Build Construction Crew Series: Each of these sets comes with K'NEX parts, including bricks, rods and connectors to build an exciting construction vehicle. There is also a K'NEXman to operate the vehicle (which I have to admit is pretty cute), and construction accessories to play with! You can build on the brick plate that is included in the set, then combine all four sets and the brick plates become your own actual construction site! Being that my kids dad is often at construction sites, this is extra cool for them.
Fire Rescue 10 Model Set: You are able to build 10 different models including a cool fire engine with this set. There are 127 parts plus step-by-step instructions and building ideas. The convenient storage box is a great place to store your parts and makes it easy for you to take the fun with you.
Both these sets were a hit at my house. Madison loved that she could use whatever they built and play with it right away. (She nicknamed this excavator the pooper scooper for the puppy).