Wasn’t sure how to share in other posts, so started a new one.
My protocol was as follows (knew there were 27 possibilities, just wanted a systematic way to make sure I got all of them)
Identify shape 1, shape 2, and shape 3 (doesn’t matter which specific shape you assign to each number
Find all possible 3 shape patterns
Find all possible 2 shape patterns with the 1st 2 shapes repeating
Find all possible 2 shape patterns with the 1st and last shape repeating
Find all possible 2 shape patterns with the last two shapes repeating
Find all possible patterns with no shape repeating
Students initially struggled with a systematic way of identifying all the possibilities. Had to stop myself from giving them the total and encourage them to think about it abstractly in more general terms. Good activity to get the kids thinking about systems and the ideas of what symbols represent