Would going from active Army to National Guard (so I can pursue college), and then going back to active hurt my career?

SGT (Join to see) I took a two year break from active duty to complete my bachelors degree and then returned to active duty. While studying for school, I was part of the National Guard in my home town. If your wanting to be commissioned, you will be fine as long as you qualify for Officer Candidate School and meet all the requirements. If you are wanting to stay enlisted, keep in mind from other posts that your current rank may not transfer back to the active component. SFC Brian Johnston states this well in this thread. Best of luck and serve proudly no matter what you do.

If your goal is to become a Regular Army NCO and have a long career then retire, then stay put! Use all the resources available to you to complete college on active duty. It's not going to happen overnight, but if you work hard and take advantage of opportunities when they are there, you will earn a degree. If you want to ETS and go into the ARNG, that's fine too. But do not assume that it will be easy to just go back to the Regular Army. There are a lot of hurdles, like getting released from the ARNG (if under contract). Also, the Army has restrictions on prior service, so your options may be limited if there are any at all. Then there is the probability of losing rank. If you are a first term Soldier, you will have lots of options an incentives to re-enlist (more on the way per Army Times). All those will be pissed away if you get out and then later want back in. Think it through carefully and do your research.

If your in for the long haul on Active Duty stay there! There is no reason to lose rank trying to get back on AD. Or possibly risk not being able to get back. If you can use online courses. I waited until I retired and was working as a contractor to start my degree. My Military experience did cross over and give me lots of credits but it still took a while doing one or two courses each semester.