Transportation Alternatives Enhancements Act This bill revises and reauthorizes the surface transportation block grant program (Transportation Alternatives Program) in the Department of Transportation (DOT). For example, states are allowed to allocate funds under the program to counties, metropolitan planning organizations, regional transportation planning organizations, and local governments. Additionally, metropolitan planning organizations that serve an urbanized area with a population of 200,000 or fewer are eligible for funding. The bill also (1) adjusts the funding limits for states to improve the ability of applicants to access funding in an efficient and expeditious manner, (2) limits the transferability of funds under the program unless a state meets certain requirements, and (3) expands the safe route to school program of DOT to high schools. Currently, the safe route to school program is carried out for the benefit of children in primary and middle schools (schools providing education from kindergarten through eighth grade).