A couple of weeks ago my model rocket club held a regional contest. One of the events was G Eggloft Altitude with altimeters. Now, usually we measure the altitude of a rocket using trackers or theodilites and reduce the angles measured with trigonometry (Science!) to get the altitude. This time we were using little electronic altimeters that record the maximum altitude and read it out in flashes, beeps, or LCD displays.
This works fine as long as your rocket doesn't land in the lake.
My rocket eventually floated close enough to the shore to be rescued. Unfortunatly water got to the altimeters and wrecked them. At least the egg survived so Bumbling Brothers Flying Circus got flight points.