A while ago we were sent some sets from Strictly Briks to play with. 
The company makes Lego compatible pieces which open up different ways to play with bricks. They specials it base plates and pieces so you can build towers, they also have letters and numbers you can use on the plates as well as a game. 
We have the Trap and Gap base plates and Brik Towers:

The Brik Trap and Gap set has two large base plates, and 2 stackable base plates plus 15 of the column pieces.  They idea is that the trap doors open so that you can push things through (such as cars!).  
The Tower set has a whopping 12 base plates and 50 stackers. 
These sets are great for anyone who is crazy for Lego and already have a collection. If you like to build towers these are interesting to play with.
A few things to point out about these sets though – on their own, they didn?t amuse my kids for long.  You do want to have other pieces of lego, esp Lego men and women to play with it (see above!) and cars too.  Otherwise you?re just building empty towers.
They also can be a little fiddly for younger kids.  There?s a knack to it as of course the tower gets more fragile the higher up you build it and even my older one got a bit frustrated if the tower came crashing down when adding another layer.
Overall though, these are great. You can get an alphabet set for this (which clicks on) which I definitely have an eye on.
Check out the brand on Amazon.
*PR Samples  

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