It is true that the Scriptures warn that taking this meal with presumption, eating as one who believes himself or herself to be in Christ, while living as though he or she was not in Christ is a damnable situation to find oneself in. But this is not a problem for children or teenagers – any more than it is for adults – for all of us.
What is a particular temptation for teenagers is to develop schisms and cliques that refuse to consider others as worthy of their time. This is similar to the situation in Corinth which Paul rebuked. Don’t come to this Table thinking you too good for others who are also coming.
And so, look to Christ as You come. Look past your baptism and see Jesus who washed You from your sins, see the Holy Spirit, who placed you in union with the Father and in the Son and with His people. Look, by means of the Word of God proclaimed, and see your heritage, your inheritance, your destiny in Christ. And then come – come little ones and growing ones and older ones – and be nourished by the Father at the Table of His Son.