Children learn by doing and seeing as well as reading and hearing.
Loyola Press has a great link to 40 Ideas for 40 Days for children.
They also have Lenten Activities for Children. This link has age appropriate activities for youth and children by grade level - through 8th and include the Sorrowful Mysteries and online Stations of the Cross.
Encourage youth and children to pray during Lent. These ideas and activities will help them to meditate and think about Jesus more and give them the tools.
Mother Mary, Pray for us to teach our youth and children to be followers. Amen.