I did this with guns and knives as a (more so guns, but still spent hundreds on knives).
I bought my first gun with my own money at age 12. It was a lot of lawn mowing and table busing to buy guns back then.
My dad gave me a Ruger 10-22 and Marlin 30-30 as my "gun starter kit". After that, I bought my own .30 carbine pistol, .30 carbine M1 carbine, Ruger Mark 1 .22, before I could drive.
I did not spend money on "toys" as a kid much. Guns and knives have always been it for me (aside from sports equipment like hockey skates, in line skates, snow board gear etc).
I never spent money on stereos, music, or "cool" clothing as a kid. I pinched my pennies worked two or more jobs all through junior high and high school.
If you are still in High school, just make sure you are a good ambassador of knives. Make sure you are not taking them where they are not allowed, or using them in a manner that will reflect poorly on you or knife collecting in general.
I, luckily, was raised in a time where carrying knives to school was common, and I always carried a knife.
Once, in 5th grade, I had a heavy machete that one of the teachers found out I had brought on a weekend camp out (a school camp).
Instead of taking it away, she was excited I brought it, and asked to borrow it for a while. I figured this was her "nice" way of taking it away from me. She actually handed it back after disappearing with it for a few hours. It was dirty, and I asked her what she had used if for. She showed me a pile of edible plants she had harvested (including cat tails, and some sort of tuber/root) for a survival demo.
She handed me the machete back for the remaining 2 days of the camp. She never once told me to hide it, or keep it out of sight.
I am only mid thirties, but that was a different time, in a smaller town.
I did a demonstration in JR High where they let me bring several firearms to school, and check them in, for a demonstration.
Just a different world. Now, at those same schools, any knife is a weapon and will get you immediately suspended, and possibly permanently expelled. (one of the things that has changed since then, is our small town was one of the first towns in the country with a bad school shooting. Several killed by a trench coat wearing kid years before Colombine).
My point is, Don't loose your knives by taking them to school!
My other point. I still have all those guns, and most of those knives. All are still working (except a few knives I abused, broke, gave away, lost, or sold (or had stolen).
The guns are all worth more today, then when I bought them (some by several times their price).
The one custom I bought back then is worth at least 3x what I paid for it (but I will never sell it, because it was made by my uncle, and he died quite a few years ago!).