Below are a few tried and tested ways to improve your attention span:
Meditation to the brain is equal to that of weightlifting to the muscles. Meditation trains your brain to hold your attention for longer periods than before. That is because meditation involves exercises that train you to focus your attention for prolonged periods of time. Mindfulness and meditation classes are rampant these days, so you can choose any that you like.
If you do not have the time or budget to attend an actual class, try researching some breathing exercises and simple meditation exercises that you can do any time of the day.
Similar to improving your memory, exercise can also improve your focus and attention. The rationale is the same as that of memory improvement. Exercise increases blood flow to the brain and stimulates neural connections that are vital to brain function. Brain function is inclusive of not only memory but also focus and attention, so you get the best of both benefits with exercise.
Taking notes by hand is said to improve your focus and attention as well. Contrary to typing on a laptop, taking notes allows the writer to pick out vital information to write down, taking on the most important aspects of a discussion, and thereby doing a lot more of information processing than just by typing a statement word for word.
Another trick to improve your attention is to take active participation in a discussion. Asking questions prompts your brain to make analyses and connections between information being shared so that you not only improve your focus on the subject matter at hand but also delve deeper into it. Asking questions tends to peak your interest during a conversation so that it feels that you are effortlessly interested in a subject, and thereby increasing your attention towards it.
L-theanine is an enzyme that is specifically found in tea that stimulates the center of the brain for attention. Unlike coffee which perks you up, tea actually helps you focus. There are a few studies that support this, but it would not really hurt to give it a try. It might be that the relaxing properties of tea clear your mind of the clutter so that you can focus on what truly matters.
Gum makes you more alert and increases your attention. While it may seem quite tricky that a piece of sweet can do this, it is scientifically proven that chewing alerts your brain by signaling it that nutrients are on the way. In a way, you are somewhat tricking your brain into alertness. If you are stuck in a boring but important class, you may want to pop that gum out, and even share it with the class.
Classical music to be exact. If you have not been listening to it, now might be a great time to start. Symphonies and their sweet melody can help stimulate your brain, and the little pauses in between movements actually keep your focus suspended in anticipation to the next. Listening to classical pieces in generally good for the brain, it is even recommended for fetuses and young children to develop theirs.