Gredler et al. have designed an educational exercise for observing selection for increased frequency of an allele ("red eye color" in the figure below) in a population and demonstrating that linked molecular markers also increase in frequency based on their chromosomal distance from the eye color gene.
The experiment was described in the paper "Revised college genetics laboratory exercise for witnessing phenotypic and molecular evolution in the fruit fly". The strains for the exercise are shown below.
IMPORTANT: We lost one of the stocks for this lab in 2021 (60740 w[1118] Mi{GFP[E.3xP3]=ET1}MB05922/Dp(2;Y)G, P{hs-hid}Y) and replaced it with a stock carrying the same insertion but lacking the hs-hid on Y (25312 w[1118] Mi{GFP[E.3xP3]=ET1}MB05922). Note you must therefore collect 25312 virgins "manually" . . .