As you can see from the pics, blocks go with all sorts of other toys. And the the golden rule with wooden blocks is: more the merrier. But as any trip to a traditional toy store will tell you, they are ridiculously expensive for a piece of dead tree. The solution is to buy starter sets of blocks with a range of shapes, then supplement the collection with DIY blocks. Go to you local hardware and buy lengths and shapes of different sizes. Hardwood is best, but pine is also fine. Cut them up with a power miter-saw (simple 90 degree cuts), doing as good a job as possible to make the lengths a standard size (eg what is common in the starter set), as well as some blocks of double-length. This will give you, I mean your kid(s), the most flexibility when constructing. Use a hand sander to smooth the blocks off. There is no need to paint or lacquer them, unless you have the time and energy (although that makes a great extra Dad/Kid project). Wooden blocks are so hardy, that even with an intensive builder in your midst, your grandkids will eventually be playing with them.
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