First Communion and Confession are definitely special events, and the gifts others have mentioned here sound like wonderful opportunities to convey the events’ importance to your child.
One caution, though: At my parish, the priest has a tradition of inviting the First Communicants up to the sanctuary to answer questions in front of the congregation, such as “Is Christ really present in the Eucharist?” In response to his question “Why are you so excited about receiving the Eucharist today?”, one particularly eager boy answered, “Because we get money and gifts!” The congregation and the priest grimaced–and I’m sure the child’s parents did too! So be sure your child understands the priorities of the event, and make sure the gifts are relevant and useful to the child’s spiritual life.