UPDATE: In case anyone reads this in the future, all seedlings survived my vacation. What I did is bottom water them thoroughly so that the soil was completely saturated and then put a pane of glass over the pots covering ~80% of the surface area. My thinking on this was that it would allow moisture...

Tricky.. How about: water them well (but not so they are too saturated), keep them cool and part cover them, e.g. a clear lid with a bit of an air gap? In 10 days they could die of dehydration at this age, or from mould/fungus, but if they are moved somewhere with temperatures around (say) 15deg C ...

Help! I have some seedlings ~3 weeks old and I'll be going on vacation for 10 days later this week. What should I do with these little guys? Was considering covering the pots with plastic wrap to make sure they don't dry out, but they're not currently in high humidity so not sure how well that would...