Central location for school, work, and home in London?

Hello, all. We are moving over for a year with our kids (and our dog). I'm overwhelmed at the magnitude of the move for just a year, but hopefully it will be a wonderful experience. My husband's office is at the Euston Station, we're applying at Southbank, Int'l Community School, and maybe the Int'l School of London. We're heading over in 3 weeks to scout areas and look at schools. Can anyone help me with areas that would be on a direct tube line from Euston and close the schools? I've made myself cross eyed looking at the transit map and the london and map and trying to figure out what's what. This is all fairly fast and I could use all the help I can get.

Many, many thanks!