Around 50 teachers from Dalit and other marginalised sections took out a march towards the President House on Friday to demand that B.R. Ambedkar's image should be on currency notes and April 14 -- Ambedkar's birth date -- must be a national holiday.The teachers marched from Samta Sthal, the resting place of former Deputy Prime Minister Babu Jagjivan Ram. They were barricaded from reaching the presidential palace. Members of Delhi University SC/ST OBC Teachers' Forum and others from schools submitted a memorandum to the President's office.