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Almost any lab that is usually designed as a "verifying" experience can be recast in a "discovery mode" with a little thought. For example, the conservation of momentum can be done by looking at a whole bunch of collisions using motion sensors, calculating the before and after momentum of each collision and graphing the befores vs. the afters. Fitting a straight line to the data should yield a line with a slope of 1 and passing through the origin. This can be done fairly early in the momentum sequence--before one talks about conservation of momentum, so they have in fact "discovered" the principle, and in the process seen that there is a good bit of "experimental error" since the slope will never be exactly 1, nor will the intercept be exactly at zero. But in zero net momentum collisions, you don't have to worry about percentage discrepancies around zero.
Are we sure that there is NO educational value in "verifying" labs? That's a strong claim, and if it is true, I am troubled to hear it because I sure do a lot of them in my first-year high school physics classes.
For example:
We use motion sensors to get velocity data to see if momentum is conserved in a series of collisions. We also check if energy is conserved, and if not, we calculate the fraction that is "lost" in the collision. Is this a pointless exercise for a first year class?
Or here's another: we just used resonance with tuning forks to find speed of sound. Oversimplified? Yes. Handed correction factors without explanations...guilty. But this is a first-year, non-honors class. I think they are more likely to believe and remember what resonance is after raising the glass and hearing the tuning fork magically amplified by the resonating column of air.