The course you paid as an employee is a job-related expense.
Up to tax year 2017, job-related expenses are deductible as an itemized deduction subject to the 2% of AGI floor.
Under the Tax Cuts and Jobs Act, the itemized deductions for job-related expenses subject to the 2% of AGI floor are suspended for expenses incurred after December 31, 2017 through 2025.
Therefore, your summer course is no longer deductible for tax year 2018.
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