To emphasize that all such expressions produce the same graph, you will want all groups to use the same scale on their axes. One effective way of doing this activity is to provide each group with a blank sheet of transparency film and have them graph their solution. Then lay the transparencies on top of each other on the overhead projector so that it is clear that all the graphs are identical. For some classes, it may be appropriate for each group to determine its own scale and compare the graphs. In this case, it may be more challenging for some students to see that all the graphs are actually identical.
Students can investigate interchanging uneven numbers of frogs.
The following table shows, in more detail, the number of moves needed for the first several situations of this type. Students can come up with their own rule.