For me high school happened in the early 2000s. I was already well versed in computers thanks to my interests and having one at home since the mid-late 90s. Computers and the Internet were becoming mainstream but still seen as nerdy by most. Having a home computer meant your family was well-off. I was the 'cool' kid with cable Internet and a CD burner at home. Informal 'computer clubs' of sorts formed around the school's computer lab, irrespective of the teacher knowing anything about computers. Most high schools in my area didn't have a computer literacy curriculum or had a woefully inadequate one, so you were on your own. Flash cartoons were a popular attraction for non-nerds at the school's computer labs. Encarta and some local encyclopedia software was our copypasta source for lazy homework.
During my high school experience the technology landscape changed considerably, along with its mainstream acceptance. When I started high school VHS tapes, CRT TVs and overhead projectors ruled the classroom, when I left, DVDs, laptops for the teachers and LCD projectors were catching on. Kids/teenagers didn't have cell phones. I had a hand-me-down D-AMPS brick which I didn't bother carrying with me most days. Minutes cost a fortune, none of your mates had one, taking it to school was a sure way of getting it stolen or confiscated. That quickly changed when cheap PAYG feature phones hit the market, along with school policy which started semi-tolerating the things. I finished HS with a cheap monochrome LG CDMA flip phone which I still didn't use much. 😜
Flash/HDD MP3 players also were too expensive at first for the average teenager, cheap Walkmans and Discmans from the 90s carried on as the popular choices for music on the go. MP3-playing Discmans were briefly popular during my HS years as sort of a stopgap solution. I started HS with a cheap Walkman and left with a cheap S1-based MP3 player. My portable gaming needs were satisfied by a Game Boy Advance and pockets full of AA batteries and cartridges.
Digital cameras were barely starting to become popular during my final years of HS, decent ones were pretty rare. Cheap horrible ones with webcam-type sensors, 7-segment displays and battery-backed volatile memory were popular and thus the majority of the pictures of that period were captured in such craptastic quality. When someone brought a real digicam to school it was quite an event.
I feel like when I started HS the whole 'techno-clueless' mainstream culture from the 90s was still going strong, when I finished things started changing, and to me it felt like two different eras.