With the spring semester gearing up, you may once again find yourself with idle, half-hour blocks perfect for aimlessly browsing Facebook. But what if you had something useful to do instead? Here are some suggestions from HackCollege.

One: Read a book.

My school requires four semesters of Great Books Seminar courses, which means that first- and second-year students have to dedicate a few hours each week to reading books and plays. Most people leave their reading until the night before class, but a friend of mine had a better solution: she carried the week’s reading with her wherever she went. She read in line, in between classes and whenever she had a few minutes of downtime, which saved her two or three hours of free time every Sunday.

Whether it’s required reading or just personal enrichment, carrying a book (or a Kindle app) can put previously wasted time to good use.

Two: Explore.

Your campus is probably full of hidden gems (or at least cool spots you’ve never noticed). Taking a quick walk around helps fit exercise and fresh air into even the most packed schedules. And, if you find a good new spot, you can do some of the other activities on this list there.

Three: Chill.

Netflix, Pinterest, Facebook…whatever you enjoy, relegate it to the awkward in-between times. Don’t wait until you get home; you’ll have more time for homework and bigger, more important tasks if you leave your home time free of these activities (at least for the most part).

Four: Work.

Conversely, if you’re in the zone during the school day, doing your homework and other tasks between classes might be more productive and make you feel less guilty about watching movies or going out in the evenings.

Five: Take a nap.

We’ve written about the science of napping before. Finding a quiet spot (in your dorm, in a campus lounge or even in your car) to power nap means you’ll be bright eyed and bushy tailed for classes and homework later on.

Six: Make some money.

Whether through an on-campus job or a side gig, who could say no to changing extra time into extra cash?

Seven: Meet up with friends.

Is your class schedule crazy? Do you spend evenings dissecting Locke or memorizing organic nomenclature? Use the time between classes to grab coffee or a sandwich and keep in touch. Your friends will enjoy it, and you’ll get a break from your academic cocoon.

Eight: Chat with professors.

One of the most common academic tips for college students is to peruse office hours. But in the absence of pressing course-related questions, visiting professors can seem like a daunting task and a low priority. If you have a few minutes, swing by anyway to say hello and chat. It will make visiting your professor with harder questions later down the road easier, and you might learn something to boot.

Being conscious of and using the time you have between classes can not only free up larger blocks of time later on, but can add unexpected perks to your day.