Using http://doc.qt.io/qt-5/qml-qtquick-controls-calendar.html, create an activity where the child have to select some specific days:

• find the october month (within a given year).
• select the third monday of october or select the 02/05/2016 (be careful, depending on the country, it may be 5 Feb or 2 May).
• click on next Sunday after the second day
• having events on some days and need to choose the asked one...

We need to check that the calendar will be translated with the current locale (and if it uses the selected font too if possible) and potential issues depending on the platform (may not be displayed the same depending on the OS).

links:
dayOfWeekFormat can be used to increase the difficulty on higher levels.
http://doc.qt.io/qt-5/qml-qtqml-date.html#toLocaleString-method may be useful.
http://code.qt.io/cgit/qt/qtquickcontrols.git/tree/src/controls/Calendar.qml calendar code.
http://blog.qt.io/blog/2014/06/06/qt-weekly-12-qt-quick-controls-calendar/
http://doc.qt.io/qt-5/qtquickcontrols-calendar-example.html