I don't know exactly what to make of this because it does look like a big effort was made.
Writing:
The joke delivery was pretty bad but I guess that's my opinion. However, the way the characters acted didn't make too much sense. Who realistically reacts in great wonderment upon finding a slightly exotic tree? People plant exotic trees all the time.
Do the characters have ADHD too? Who goes "This day keeps getting more and more interesting!" when a part of the city just blows up on front of them? Does that other guy really wants to spend his day studying the tree when he can just google about it? After all, it's got a name according to a character, it's not a new tree. For a "look at how smart he is" kid, he isn't all that smart.
The worst part of the writing, in my opinion, is the fact you made yourself the main character. Self-insertion is a BIG bad writing flag for me.
Visuals:
The pseudo-anime style was pretty jarring to look at, specially considering the copious amounts of tweening and the out of place poorly rendered 3D backgrounds. If you insist on not drawing the backgrounds, at least make em fit the aesthetic. Try more cel shading and less melting textures.
I feel like a lot of the 5/5 you're getting is because kids and teens tend to mistake "OMG Anime look! OMG 3D graphix, only pros can do that!" with actual quality when neither of these things are hard to accomplish these days.
Also, what's up with the realistic-ass explosion on the google maps?
Sound:
Not much problem here.