Take a clean, clear bottle, put some things inside and then fill it the rest of the way with filler.
This one has random things from around the house. There is a golf tee, safety pin, fuzzy balls, pipe cleaner, plastic flower, and a bread bag tie.
For filler I used some old beans that I had sitting around.
Secure the lid tightly and you are all set!Some other variations include choosing a theme for the included objects. You could put in little letters, stick to a color theme, make a beach bottle - maybe even with a message?
Fillers can be anything you have around. Sand, beans, noodles, and rice work well. I've also made a set of the bottles filled with water.
Another possibility is to make a card listing the items included in the bottle for the child to refer to.
Small versions can be a great toy to take along in the diaper bag to look at while at the Dr.'s office or waiting in line. A big one (2 liter) can provide a real challenge if filled with the whole alphabet and a few surprises!