Students were put in random groups of three (10 groups in total) and were given a vertical 4 ft by 8 ft sheet of white board to write up their solution. I asked them to write it out so someone could come along and read it and understand it. Groups were given about 50 minutes. After the time was up they paired with another group. Each group read the other groups solutions and asked them clarifying questions and then revised or added to the solution in a different colour.
I am going to group photos of student work by type of solution. This is a sample of the work from two classes of 30 students.
Solution 1 Happens 11 times over the 12 hours so.....12/11 hours in between each time.
Solution 2 Using the intersection of the two trigonometric graphs. No groups actually finished this idea.
Solution 3 Splitting the twelve hours up 11 times like solution one. Realizing it is not perfect and taking the missing time and dividing it up 11 times and adding that part in along the way. In other words using our error or mistake and adjusting the answers. The first group divided the missing 25 seconds by twelve instead of eleven.
Unfortunately this group erased their original times which was out by 25 seconds. They then used this to adjust the times.
Solution 6 Using some equations to show where the hands are and equating them.
Solution 7 Plotting degrees versus minutes for both hands and using the intersection of two lines.
This was well worth it. From my perspective we hit the following process expectations:
Now if I could just do this everyday..........
On a personal note I was thrilled with some of the approaches.