I understand that this may not be what you want to hear, but the best musical education would be hearing mum and dad play stuff around the house. Particularly if others are invited round to join in. A kind of 'home session' where the kids are allowed (definitely not forced) to sit in is the perfect environment for them to learn music. If, in that environment, they don't bite then they are not destined to be musicians. If it does and instruments are left handing around kids will pick up playing on their own if they want to and if the home sessions are fun they will want to.