I think a commute from Woodbridge into the City every day would be a slog. Doable but a total slog imo. I would look at villages close to Manningtree which is on the right side of town for the girls school (which is in the middle of no-where). Ipswich School publishes the school bus routes on their website which might be a good starting point? Personally, while I would love to live in a cosy Suffolk village if I had two soon to be teenagers to ferry around, I'd try to find somewhere as close to the school of my choice as possible, and move to the sticks as soon as they can drive. £500-600k buys you a lot of house in Ipswich, in the nicest part of town, on the doorstep of Ipswich School.
We live near Chelmsford at the moment but are looking to move to Suffolk to be closer to older parents (in North Norfolk) and for the schools options (We are looking at Ipswich School and Ipswich High School). I work locally but my husband commutes to the city.
What towns and villages would be worth a look? Ideally with a train station nearby and a nice spot for children to grow up in. I like to be able to walk to a couple of small shops and at least a pub would be nice. We have previously looked at Dedham but I know it's not cheap! Our budget would be 500-600000, but we don't need a mansion.