The Mutter Museum of medical oddities is full of the grotesque and fascinating bodies and viscera and skeletons of those with bizarre medical conditions. At the back is an accessible entrance with an intercom camera, where a security guard will escort wheelchair users through an accessible elevator that can reach both floors of exhibits.
The Rodin Museum is similarly only accessible through the back entrance in which one needs to ring a bell for a worker to come and guide you through the accessible pathway.
The Franklin institute is built specifically with young kids in mind. There are a lot of hands on exhibits one can try that will teach some key scientific principles. However, keep in mind that while you can go to all exhibits, some hands on activities may not be accessible.