I feel very overwhelmed, particularly with teenagers; they are ungrateful and disrespectful. What should I do?
Raising, and working with, teenagers has both its tremendous challenges and its wonderful rewards. Thankfully, the Bible has practical, real-life instruction for both. Remember that while children (including teenagers!) are a blessing and a gift from God (Psalm 127:3), we must also be careful and good stewards of these gifts.
While we certainly must be concerned not to unnecessarily provoke our children to anger or frustration (Ephesians 6:4), we also have to remember that we are commanded to instill the wisdom and truth of God's Word in them, not just leaving them to their own opinions or habits: "the rod and reproof give wisdom: but a child left to himself bringeth his mother to shame" (Proverbs 29:15).
Ultimately, only God can touch and turn the hearts of your children. Therefore, there is nothing more helpful or appropriate than praying diligently to God for them on a daily basis. This is a vital ingredient of raising children that is often forgotten or neglected in the midst of the daily hair-pulling and hubbub. As you pray for them, you may also find that your own heart is drawn closer to them and to God.
May the Lord bless you to enjoy the wonderful blessing of the children that He has given you, while also prospering the hard work that it will take from you in order to teach and train them.