It escapes me where I first heard a quote, the gist of which is, "Inch by inch, it's a cinch; yard by yard, it's really hard." I just read and posted a terrific "USNews" article about "Healthy Study Habits for Teens", which outlines setting a schedule, eliminating distractions and breaking up larger assignments and study sessions into smaller pieces.
When I used to work for IBM, they hired the Franklin (now Franklin-Covey) Planning team to teach us how to "do time management." This could not have been inexpensive. I faithfully used my Franklin planner for years and it worked for me. I now use an online calendar and to-do list.
Whenever I meet with students, I outline the process and timeline we will follow for their college search and applications. One of the first things we discuss is, "How do you keep track of things (assignments, deadlines, appointments, etc.) now?" Responses usually vary from "writing it on my arm," to using the day planner received from their high school, to using a smart phone, to a vague stare back.
If a student is not comfortable with time management, the college application process is a great place to start! In college, the daily assignments they are used to in high school are usually replaced with one or two larger tests or papers. Finding the system that works best for them before they head to college ups the "cinch" factor!