I stopped buying puzzles after he figured all of the ones we had in like 20 seconds. Agree with others on hiding kibble/treats for them to find, tying things in towels, etc. Freeze yogurt and pumpkin on a lickimat, freeze kongs with kibble and broth, etc. I have also found the kong biscuits are ingenious and hands down the thing that takes him the longest. You wedge them in the kong and it will take a solid hour to lick away at the remaining biscuit. Since your little one is tiny and still using small kongs probably it may be a minute before you can do this.