Work of some kind would certainly help to keep these young men occupied part of the time, but the real problem is the gender imbalance in the migrants. I understand tht 70% are single men without their families.
Part of the answer will be to only take in as many young unattached men as women and give priority to family groups. This will cause some problems but will solve others. Many men will choose to come in as a part of a family group, others will need to stay in refugee camps close to their home country.
One cause for concern already is that when the Syrian situation is resolved and the many Syrian refugees in camps along the countries borders return home they will have the reverse of the problems European countries are now, by having too few young men. The rebuilding of the country after the war will require the young and fit and those with professional qualifications, the ones most likely to make it to Europe. The refugees going back will be disproportionately, the old, the very young and women.