The families of Mohammed Nahin Ahmed and Yusuf Zubair Sarwar urged both men to return home when they realised they had gone to fight in Syria.
Sarwar's family reported him missing to police in May last year after they found a hand-written letter from him in which said he had left to join a terrorist group called Kataib al Muhajireen (KaM)- later renamed Kateeba al-Kawthar - "to do jihad".
Days earlier he had told his family he was travelling to Turkey as part of a two-week trip organised by Birmingham City University, where he was a part-time computer science student.
West Midlands Police said the men showed the mind-set to go and join the jihad in Syria, before carrying out research, buying equipment, and finally travelling a well-trod route to get inside the battle zone via Turkey.
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The victims were collecting permits and escorts a day after their home town was liberated from the extremists.
Scotland Yard said the male youths will appear in custody at Westminster Magistrates' Court on Saturday.