im in such a situation my self currently 
theres this class-related project, person A wants to take it up but
the class doesnt seem so happy, so i stepped up and discussed about
me taking it up, the class agreed.
and so i took up the project( to do something for the class)with
two other classmates who said they'd assist me. and so we did our
proposals and did the survey and stuff.
so things did not turn out well as time was running out(holidays.)
and hence our project had to come to a stop.
Now the new year is beginning(same class) but i realised from last
year, that my two classmates arent willing in helping me out and
the class doesnt much listen to me(i have to have their
co-operation for this project.)
So i decide to drop this project afterall, and hand it back to the
person who wanted to do it at first next year.
i intended to :
1. to do an apology infront of the whole class, say sorry, tell
them i couldn't do the project well and give a big bow.
2. hand the project back to person A.
But now person B, whom i've recently worked with for several
projects(which turned out quite well) wanted to help me in the
project.
So i intend to:
1 .Continue doing this project, but together with person B.
i'd say an apology to the person/people involved is all u need.
Though it'll be embarressing, but think about it, people will know
u're not playing or fooling around but mean serious matter
here.
Good luck to you. 