LH gives out a variety of packages which are age appropriate, ranging from babies to tweens. CX has given out Disney themed packages on flights to HK. CDG gives out Mickey themed travel books at security, and as is common in France families with small children in general are given priority treatment. LX used to give out chocolate during the flight and on deplaning (not sure if that is still the case as I haven't flown them this year, but it was for all kids, big and small and adult)
Generally, most European and Asian carriers are child-friendly and may offer up an activity. But I would caution anyone not to expect special treatment just because they are travelling with children.