1 янв 1841 г. - Classroom Chalkboards
Описание:
While classroom chalkboards were introduced in 1841, it was not until the end of the 1800's that they were included in all schools. Horace Mann was a major advocate.Добавлено на ленту времени:
Дата:
1 янв 1841 г.
Сейчас
~ 184 г назад