Describes a coating composition for the preparation of abrasion resistant coatings consisting essentially of:(a) 5 to 35 weight percent of a silane monomer mixture of (i) C.sub.1 -C.sub.12 alkyl tri(C.sub.1 -C.sub.6)alkoxysilane and (ii) tetra(C.sub.1 -C.sub.6)alkoxysilane, the weight ratio of (i) to (ii) being from 3:1 to 1:3;(b) 1 to 9 weight percent of polyvinyl alcohol that is at least 72 percent hydrolyzed;(c) a solvating amount of lower aliphatic alcohol;(d) a catalytic amount of water-soluble acid;(e) a leveling amount of nonionic surfactant; and(f) water in an amount sufficient to formhydrolysates of the silane monomers and to solubilize the polyvinyl alcohol and acid. Further described are transparent articles and photochromic articles comprising organic polymeric host material, organic photochromic compound(s), and a cured abrasion resistant coating prepared from the coating composition.