If your child is just learning to count money, I would make caterpillars with coins of just one type (i.e. all pennies or all dimes). When first introducing mixed coins I would leave out quarters at first.
Check out the post at Deceptively Educational to see how she made cute caterpillars with pipe cleaners. Her suggestion of using a hundreds chart would be helpful if your child is just starting with counting coins.http://deceptivelyeducational.blogspot.com/2011/07/counting-money-with-coin-caterpillars.html
Also check out Miss Kindergarten for more info and a free printable at: