- Hours Tues.-Sat. 10 a.m. -5 p.m. Sun. 1-5 p.m. (Mon. 10 a.m.-5 p.m. when school is out) Plan your visit Admission Adults/Children: $5 Seniors: $4 FREE for museum members and children under age 1 280 Marcy Street Portsmouth, NH 03801 (603) 436-3853 The Children's Museum of Portsmouth is a hands-on arts and sciences museum for children of all ages offering engaging exhibits, daily art and science ...www.childrens-museum.org