This book by Leo Lioni was shared by Carol Stafford at an in-service a couple of years ago that has become a favorite of mine! Carol used rocks and pebbles to paint letters on the rocks and had the kids put the alphabet in order or build words with the pebbles.
I decided to use the Dollar Tree's glass pebbles and paint numbers on them.
I created some sheets to use with the numbered pebbles where you can have the kids order the numbers from least to greatest, greatest to least, add and subtract, or decide greater or less than. You could also have them pick out numbers and create the greatest 3 digit number if you'd like.