The Trailer Safety Improvement Act would require states to include education about trailer safety in their highway safety programs that receive federal funding. The bill specifically directs states to focus on preventing improper and unsafe use of light-duty and medium-duty trailers and educating the public about required safety equipment and preventive maintenance. This legislation affects state transportation agencies and the general public who use trailers for personal or commercial purposes. The bill does not specify new funding amounts or implementation timelines, but instead amends existing federal highway safety grant programs to incorporate these educational requirements.