Parents ask this constantly, and the honest answer is: it depends enormously on the child. Ghibli Park is not built for children in the way a conventional theme park is. It rewards recognition, patience, and looking — three things not every eight-year-old brings to a day out.
Who it works brilliantly for
Children who know the films. That is the single biggest predictor. A child who recognises a room, an object, a creature will light up repeatedly through the day. The park is essentially a series of recognition moments, and recognition requires prior knowledge.
Who struggles
Younger children with no film familiarity, and children who need physical stimulation. There are no rides to burn energy on. The walks between areas are long and wooded. A child expecting a rollercoaster will be bored by mid-morning, and no amount of parental enthusiasm fixes that.
Watch two or three of the relevant films in the weeks before the trip. It costs nothing and transforms the day from a walk in a forest into a treasure hunt.
Structuring the day
Anchor on your one timed indoor area, then let the free Expo parkland do the rest of the work. It has lawns, ponds, wide paths, and space to run — the release valve the ticketed areas do not provide. Pack a picnic; the lawns explicitly welcome it and the park's food outlets queue badly at midday.
Practical notes
Strollers are manageable but the distances are real. Toilets are plentiful and clean. Bring water in summer — the walks are shaded but Aichi humidity is serious. Coin lockers exist but fill fast.
The verdict
For a film-loving family, it is one of the best days in Japan. For a family looking for a generic theme park because it is raining, it is an expensive walk. Choose accordingly.