How Forms and A, B, C Years Work in AO for Groups?

It looks more confusing than it is.

Let's say you're starting a new co-op with 5 or 6 families. You sort students into Form 1 (grades 1-3), Form 2 (grades 4-6), and Form 3 (grades 7-9). The first year, everyone does Rotation A, so your co-op roster might look like this:

Form 1 A Hannah age 6     Riley age 6 Kwon Ji-Yong age 7         William age 7 Fiona age 8 Khumar age 8

Form 2 A Davina age 9 Joseph age 9 Ryan age 10 Zoe age 10 Elsa age 11 Lawrence age 11

Form 3 A Nevaeh age 12 Samuel age 12 Sarah age 13 Lamar age 13 Diego age 14 Lucy age 14

The following year, everyone is a year older. A couple of younger siblings have finally aged into Form 1, and some students have moved up to the next Form. Diego and Lucy have moved up to Form 4 (we intend to have a Form 4 for them by then!) In this second year, everyone does Rotation B. This year's roster might look like this:

Form 1 B Mateo age 6 Marisela age 6    Hannah age 7 Riley age 7 Kwon Ji-Yong age 8      William age 8

Form 2 B Fiona age 9 Khumar age 9 Davina age 10 Joseph age 10    Ryan age 11 Zoe age 11

Form 3 B Elsa age 12 Lawrence age 12    Nevaeh age 13 Samuel age 13 Sarah age 14 Lamar age 14

The year after that, some students have moved up and a couple of new students have become old enough to start Form 1. Sarah and Lamar have moved up to Form 4. This year, everyone does Rotation C.

Because some students are joining in or moving up at different times, it's more necessary than ever that students keep some sort of timeline. Students in schools that work this way don't have a problem keeping their eras and times sorted if they keep a timeline or Book of Centuries.

Form 1 C Katie age 6 Michael age 6 Mateo age 7 Marisela age 7    Hannah age 8 Riley age 8

Form 2 C Kwon Ji-Yong age 9         William age 9    Fiona age 10 Khumar age 10 Davina age 11 Joseph age 11

Form 3 C Ryan age 12 Zoe age 12 Elsa age 13 Lawrence age 13    Nevaeh age 14 Samuel age 14

The co-op or school is now starting on its fourth year (can you believe it?) and the cycle starts over again, with everyone repeating Rotation A, but some students have moved up and others have joined, so no student is doing the same thing over again. Nevaeh and Samuel have moved up to Form 4.

Form 1 A Lamar age 6 Johnny age 6 Katie age 7 Michael age 7 Mateo age 8 Marisela age 8

Form 2 A Hannah age 9    Riley age 9 Kwon Ji-Yong age 10        William age 10 Fiona age 11 Khumar age 11

Form 3 A Davina age 12 Joseph age 12 Ryan age 13 Zoe age 13 Elsa age 14 Lawrence age 14