Ummmm....actually....I'd look for a different place for lessons. But YES it IS totally appropriate that children of certain ability levels get grouped together. If the rest of the group is at one level it's reeeeaally common for a child at the bottom to get moved down a level or at the top to get moved up a level. Even if by the "level guide" the higher or lower level swimmer fits, where the group is at overall can & should be a big determining factor. This is a common thing especially for the beginning and end of summer. If someone has been the the begining class for two months they're going to be at a differnt place than a child who just started last week.
Why I say a different place for lessons is this: It sounds like this place is missing at least one level if not two.
Where I've done lessons, there are usually two "floater" classes (aka JUST beginning). The first floater class are the 2-3 year olds and the 2nd floater class are the 4-5 year olds. Even though what's being taught is the same (blowing bubbles, intro to face in the water, kicking, floating, monkey walking along the wall, holding onto the instructor -motorboat & other games-, holding breath, gliding to the stairs, etc.) the developmental levels are NOT the same. Honestly the youngest kids aren't super capable of listening, and the older kids tend to spend half their time with their ears under the water...so while both groups may not be listening, they're doing it for different reasons. Even for a good instructor, that can be very very difficult. Very difficult in the water translates to not safe. Hence splitting the ages within a beginning or adv beginning group.
What to look for in very beginning lessons
- No more that 3-4 kids in each instructor's group
- Lesson taught 90% on the stairs, so the kids can be in the water but resting/playing in the water (so they're learning comfort in the water as well as resting) between one on one time with the instructor.
- Fun
- Group activities on the stairs (blowing bubbles, songs, etc)
- "Swimming" one on one with the instructor.
- No just beginning swimmer ever more than 6 feet away from instructor.
- Appropriate age/level grouping (aka, don't put a six year old in with the 2 year olds...or have someone who can swim on their own in with kids just learning to not be afraid of getting their face wet)
- Appropriate levels (aka, not having the steps between levels be so big that it's a shock to the kids to move up and down between them...aka if one level expects kids tp be able to swim across the pool on their own, the level before that actually taught them how to do that...not just had them use a kickboard across the pool.)
Kids get moved up and down levels ALL the time, it's nothing to be embarrassed about at ALL. Why I say to look for a different class though, is that it sounds like there's inappropriate age grouping/ level jumps (there *should* be a level in between where your son is and the mommy&me class), and the instructors don't seem to be super qualified...if they're having to rely on PARENTS objecting that the way they've ordered their class isn't safe. They should be good enough at what they do that THEY catch that first...not worried parents.