Using coins to teach probability is by no means unique, and I've not really done anything that's worthy of mention, just that I've added well organized data tables that includes space for a lot of practice calculating probability percentages. I also make sure that students can apply the concept of expected outcome. They compare their data to what is expected, pool their data with others, and see whether the data get closer to the expected.
This free download includes: A four-page student handout that has 6 prelab questions, procedures for both a 1-coin toss, and a 2-coin toss, data tables to record all the coin tosses, and 6 post-lab questions. And last, the download also includes a teacher answer key.
I am also inviting people who have done this lab to post their results on my blog:
so that we can pool our data there! Please come enter your results.