Hello all! I have been pondering this dilemma for a while now and while I know what the answers will be (or at least have a rough estimate of), I thought it best that I still seek advice/thoughts from others. Sorry for the long post but I had to get this off my chest

I declared my major in math very late into my undergrad career (roughly as a junior) but I have secured funds to stay on for hopefully a fifth year to finish my math degree. The reason I declared so late was because of my strong aversion to any subjects that remotely involved math. Growing up, I was told by many people that I had a talent at mathematics and this could be seen by the fact that I was invited to do math courses done by high schoolers (algebra 2 and geometry at the time) when I was only 7 years old. Long story short, I transferred schools and suffered through a string of HORRENDOUS math teachers from 7th grade all the way to 12th grade. Suffice to say my interest in mathematics obviously quickly faded and become a hatred and my grades in math subjects turned into Ds and even Fs. It is an enormous understatement to say my math teachers were horrendous.

Anyways, fast forward a couple of years and I arrive to college and pick earth science as a major because I had no direction in college or in life. I went through 3 years of horrible grades because I simply did not like the subject and because of this my GPA stands at an abysmal 2.78. It was rather ironic in the fact that I achieved the greatest happiness of my life while suffering through depression caused by my lackluster GPA by discovering, or rather rediscovering, my passion for math after taking the mandatory calculus class required for my earth science. As of now, I have taken a fair amount of advanced math courses and I have consistently ranked at the top or near the top of my math classes with a math GPA of 3.9. I have honestly never been happier in my life than now but I am also very sad over the fact that I rediscovered my love math very late into my undergrad career.

This ultimately leads me to my question: what can I do to improve my transcript/overall portfolio when it comes time to apply to grad schools? I know that my overall GPA (2.78) is horrendous but my math GPA is a 3.9 and I have research experience with earth science and I am starting another research project in applied mathematics. I want to go for a PhD in math without a doubt but my overall grades will bar me from top programs. Would it be wise to drop my original major to focus even more on math? I am very strongly considering taking time off after undergrad to gain experience so that I may present myself as qualified applicant for top programs. I would like to have thoughts and recommendations as to what I should do because I am fervently adamant on getting a PhD in math and I simply cannot imagine myself doing anything else other than math.