Act 2 scene 3 What scheme has Romeo devised?
I do not think that you have this question quite right. Can you check and be sure that this is really the scene you want to ask about?
In this scene, Romeo talks to Friar Laurence for just a very short time. He does not really come up with any kind of a plan. The only thing he says that even resembles a plan is that he would like Friar Laurence to marry him and Juliet. It's a request, but it's not much of a plan.
Are you maybe thinking of where he plans to get a rope ladder to Juliet so he will have a way to climb up to her room?
Or maybe you are thinking of the time in Act II, Scene 2, where Romeo says that Juliet should send the nurse to find him so he can tell her what the plans are for him and Juliet to get married -- this is why he's talking to the Friar in Act II, Scene 3.
In Act 2 scene 3 of the play "Romeo and Juliet" by William Shakespeare, the author treats us to a beautiful and tradtional scene of a friar (Friar Laurence) in a colorful flower/herb garden, where the priestly man is collecting herbal products in a wicker basket. The friar wants to know if Romeo has been up all night as usual (he is concerned about any sinful or pre-marital behavior with Rosaline.) Next comes romeo's "decision" or as you call it "plan" which is to marry a new girl - called Juliet. Friar Laurence's reaction to this plan is that it is hasty and ill-conceived "he stumbles that runs fast." He tells Romeo to be wary of acting in haste - advice of course that Romeo does not take. He is too much in love to wait.