We recently borrowed this Max and Ruby book from our library, much to the delight of my recently-turned 5 year old:
Both H&F loved the idea of having a scavenger/treasure hunt so much that I made several for them this past weekend, but H's favorite by far was when I made clues using QR codes! This site creates QR codes for free. You just have to enter your text! Of course, you need a smart phone or tablet to do a hunt this way (install a free barcode reading app), but I think many of us have one or both these days! In any case, this was a lot of fun to create. What is even better, is that you can do this for pre-readers as well.
Here is one of the simple clues I made for the hunt (guess which of our Montessori map puzzles the clue was hiding in!):
What a fun way to give a tech makeover to a timeless game!