Located in Temple, Texas, this railroad and train museum was a fun morning trip for us.  They have a few stationary trains that you can climb on, look in, and even pull the bell.  With a group of little ones, we didn't go through the museum (it didn't appear to be very kid-friendly). The outside trains were the reason we wanted to visit and it entertained the kids for about an hour.  It's a fun spot to play if you are ever driving along I-35 and need a place for the kids to get out and stretch.