My 5 year old is getting Lego. Lots of Lego. It's something he loves that's he can use for years to come. Many homeschooling parents say " you can never have too much Lego" I agree. I will also get him the Lego ideas book to go with it. ( boy is that's book expensive!)
He will also get ( his birthday is dec 31!) some snap circuits. And hopefully if the budget allows a very large set of magnetic building bits of some sort. I will get Nana to buy him some boy craft bits as he loves to create stuff and we have far to much girly craft here.
and some dinosaur books. He always brings home dinosaur books from the library.
Then if I need more it will be a wood work kit, hammer nails, wheels and wood.