You and your spouse would fie Married Filing Jointly (MFJ), claim your son as a dependent, claim his exemption, and claim his 1098-T (education expenses) to apply for an education credit.
Your son would file his own return, but he needs to elect "Someone else can claim me".
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HERE for TurboTax help on Rules for Claiming a Dependent on Your Tax Return
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HERE for TurboTax information about available Education Tax Credits
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HERE for answers about claiming a student as your dependent
