We’re a big fan of corkboards as they give you an area on your classroom wall where you can pin items, without marking the original walls.
We especially like corkboards that have a second purpose like this world map version.
It comes in 16 pieces so just putting it together will be a challenge! Once it’s assembled you could pin the birthplaces of historical figures, mark the locations of world events or simply display where students have been on holiday.
If you’d prefer a corkboard map with a bit less character but a lot more colour/information, check out this alternative.