I just find the idea of muskets very strange when it comes to volley firing, even with training issues. If you have 500 troops on each side in a pitched battle with let's say 10 rows, that's 50 troops a row. Assuming that the first two rows are the only ones firing and that they switch off firing every 30 seconds (60 seconds loading time per row), that's 100 firings per minute after the first 30 seconds.

Now consider 500 troops all armed with longbows, in whatever formation, and let's say within 200 yards of the opposing army. A single volley from all the troops is 500 arrows. Let's assume that the whole army can fire an arrow every 10 seconds, which I think is a realistic number. That means that while musketeers can fire 100 shots each minute, the bowmen can fire 3,000 arrows a minute. That's insanity to me.

I've fired a bow before, and while it isn't the easiest thing in the world, I believe that a full-grown adult could easily learn within a day how to fire a bow, and at what angle he should fire it for certain distances. That really doesn't take much skill.

It just makes no sense to me why the Continental Army wouldn't have been better off with bows.

The teacher likely was referring to a letter sent by Benjamin Franklin in 1776, in which he suggests that pikes and bows be implemented as weapons.

He provides a good summary of the reasons one could think of to implement bows:

They are more accurate than muskets. They have a much higher rate of fire. Arrows in flight could intimidate the enemy and distract them. An arrow hitting anywhere puts a man out of combat. Bows and arrows are easier to obtain than gunpowder, bullets and muskets. (He doesn't note, though, that arrows take more craftsmanship and materials to make than the musket ball.)

However most military leaders with access to abundant amounts of firearms preferred to arm their infantry with guns as compared to bows. Training periods for bows, in order to build muscle strength and accuracy, could take months simply to be adequate, and training for years was beneficial to become better. In comparison, muskets require much less skill to learn.

The disadvantages of the musket's inaccuracy and slow rate of fire are lessened through massed firing techniques. The bow, meanwhile, has notable disadvantages in this situation as archers cannot fire for as long as musketeers before becoming fatigued.

In my opinion, Benjamin Franklin seems to have made good points about the benefits of the longbow. If muskets were not readily available, they would be a wise alternative. If they were used in conjunction with muskets, they could be of some benefit, as the bow has certain qualities that muskets don't.

However, if bows were truly more effective than muskets, it is unlikely that the latter would have almost entirely replaced the former by the 18th century in European armies. Ultimately, the idea was not of enough military benefit to cause a return to the use of bow.

A Native American at the time could often shoot a bow more quickly and accurately than a colonial soldier could fire a musket, due to the lack of rifling and the time and effort associated with reloading muzzle-loaded firearms.

However, the trouble was the amount of training involved. An archer would have to train for years to be effective on the battlefield, while in a worst-case scenario a colonist can pick up a musket and be able to shoot readily with proper drill i a matter of weeks. Then there's the fact that tactics of the time period favored massed formations and volley fire, which made up for the inaccuracy and long loading times of muskets.