What are vacation crafts exactly? My definition of vacation crafts would be crafts or activities that are easy to transport, require minimal setup and can be enjoyed by a range of ages without adult supervision, such that the adults can catch up with the relatives they're visiting, or have a little bit of down time themselves. With summer vacation just around the corner for many, now is a great time to start planning some fun summer craft acitivities for the kids, and I think that sidewalk chalk is a great one! (Though do check with those you may be visiting to make sure it's okay with them.)
And while the kids are out there in their pyjamas and the sun is overhead, (which in case you're paying attention means that it's at least noon and they're still in their pyjamas?) so why not have some fun with silhouettes? And come to think of it, it would also be fun to trace shadows with chalk for the starting point of a fun sidewalk chalk activity, don't you think?