For the most part this two day lab follows the 121/131 version pretty closely. The only significant differences that come to mind are:

• I don't bother with putting out any sort of ball drop mechanism. They just release by hand. In practice this is at least as good as the hokey alternatives I have tried, including magnets.
• I do not put out a supply of extra ball bearings. I instruct both students and TA's that there are 4 balls per setup (I do not use the smallest size), and the expectation is that no balls will be lost.
• I tell TA's it is ultimately on them to make sure each station has the appropriate selection of balls, and that they should put the onus on the students by telling they they cannot leave the lab until their station has been restored to its original state, including having all 4 balls. I even tell TA's to tell the students that they will lose one point (out of 8) for the lab if they fail to do this. I justify this as being part of the “Professionalism” aspect of the student code of conduct.
• Given the above I have consistently had really good experience with the lab remaining neat and orderly through out the week over all 3 quarters. Even the cratering lab, I tell the TA's that the condition of the floor is on them (and by extension to put it on the students) and it mostly works.

Other than the above I think I push the discussion of curve fitting and interpreting goodness of fit parameters harder than in 121/131. The expectation is these are physics majors who will all go on to PHYS211. Going into the subject a bit deeper is both justified and within their abilities. I tell the TA's to point out how the reduced Chi-Sq is basically the same information as the residuals, just all lumped into one number. But that it pays to look at both because you can have a “good” Chi-Sq with clear underlying systematic showing up in a plot of the residuals.