First of all it is necessary to consider about unemployment. Unemployment is considered as a serious problem.

 This one is a quickie for Indonesians who feel a strong urge to insert ‘tentang’ after consider and ‘sebagai’ after the passive considered.

• First of all it is necessary to consider unemployment.
• Unemployment is considered (to be) a serious problem.

Next time you use consider/considered, consider not using ‘tentang’/’sebagai’!