No the math is right actually, i don't think i explained it well enough though.
Highschool-Each team plays 1 game on sat and 1 game on sunday. This will be a 2 game series against another team with balanced home/away. All division rivals will play a 2 game series home and a 2 game series away during the course of the season. However non-division rivals (the 2nd division in the same conference) will play a home and away game for the sat/sun series. As explained in the previous post division rivals are played against 4 times and all other conference teams 2 times. If the teams play 2 games each week they can finish their 26 game season in 13 weeks.
Using the image above as reference. Atlanta will play Balt, Buff, Detroit, and Durham for 4 games each (2 home 2 away). They will also play Chula, OK City, Phx, San Diego, and Wichita 2 games each (1 home 1 away).
College-Each team plays a game on thrusday, fri, sat, and sunday. It has the same setup as the image above in regards to conferences and divisions so its the same deal. However they play thur-sunday 1 game a day. So the idea is to have them play 2x the amount of games. So using the same example as above just x2 each series. 8 games each against the 4 division rivals (4 home 4 away) and 4 games each against the other division teams (2 home 2 away).
Again each college team plays 4 games each week to be able to finish the season in also 13 weeks.
I hope this helps the confusion.