NOT ABLE TO ALTER DATA ENTERED IN EXCEL WORKBOOK

Using excel 2013. I was about to design Students' Attendance sheet. I typed Days: Monday - Friday in a row, then "M" (for Morning) and "A" ( for Afternoon) in the a row under the first one, then I created a grid line round the data, just to discovered that the table was already automated and could neither be selected nor be edited. When I tried to open a new sheet, the table automatically appeared in all new the sheets. Please what should I do to remove the table created automatically? Thanks.