Both paintings “Riding at the Ring” by Reinhold Timm and “A Boys School” by Francis Cleyn are located in the Ballroom of Kronborg castle

Reinhold Timm (died 1639)
Riding at the Ring, the early 17th century. Wearing Roman attire, the youngsters ride at the ring. In fact, Christian IV was himself a master of this chivalrous sport, which is implied by the conspicuous appearance on the balustrade of the royal monogram C4. The painting either refers to the third or the fourth of the Seven Ages of Man - i.e. Adolescence, Adolescence (age 15-22), or Youth, Juventus (age 23-41).

Francis Cleyn (1582-1658)
A Boys' School, the early 17th century. With their books on their laps, little boys are benched in the apse of the school building. Here they practise reading aloud under the young teacher's strict supervision. Sitting at a table, some older boys study attentively. Enthroned on the far right, the aged teacher examines a rather anxious boy in the alphabet. The scene represents the first of the Seven Liberal Arts: Grammar.