what is sota's preschool called in horimiya

Sota’s preschool in Horimiya is just referred to as kindergarten/preschool , and the sources I found do not give a distinct named school. Sota is described as a kindergarten classmate in the same grade and class as Yuuna Okuyama, which supports that he attends a local kindergarten rather than a specially named preschool.

What’s known

• Sota Hori is Kyoko Hori’s younger brother.

• He is shown as a kindergarten-aged child in the series, with classmates and a class setting mentioned.

• I did not find a canonical proper name for his preschool in the available sources.

Plain answer

So the safest answer is: it doesn’t appear to have an official named preschool in the series.

If you want, I can also point out the episode or chapter where Sota’s school is mentioned.