How to set the dates of the current monday, wednesday and friday of the current week fo date and time column for a list

Set the Sunday of current week for date and time column in a list.

Add date and time column for a list Name it as Date

Select "Calculated Value" radio button under Default value section

=1-WEEKDAY(TODAY)+TODAY

whenever u add item to this list in NewForm.aspx
by default Date=dd-mm-yyyy(21-12-2014) i.e sunday of current week


















Reference:

http://superuser.com/questions/376698/how-to-get-the-dates-of-the-current-monday-wednesday-and-friday-of-the-current