Visiting Frida Kahlo museums in one day?

I think the museums are small enough that you can buy a package that includes entrance to both and transportation. I've heard it's a good option.

Actually, the Frida Museum and House are the same, not three different museums. Walking between them would take about an hour, so it's definitely doable. I'd be more concerned about getting tickets to the House than whether it's too much to see in one day. Another option to consider is the Anahuacalli Museum, which is a Diego Rivera museum located south of the city.