This blog from Carolyn C. Brown offers week by week commentary on the Lectionary readings from a child's perspective, as well as practical ideas to use in worship. You can also search the site by Scripture reading or by theme.
This incredible site from Jenee Woodward offers comprehensive links to commentaries, images, music, sermon starters, graphics and more based on the week's lectionary readings. Scroll down towards the bottom of each week to find the specific links to children's resources.
This site offers creative worship ideas for every week of the year.
This resource from Union Presbyterian Seminary suggests children's literature which relates to the lectionary readings of the week, with suggestions as to how they might be used as sermon or discussion starters.
LightLive, from Scripture Union, allows you to access thousands of activities to use in children & young people's sessions and tailor each session to the needs of your group. You can follow the LightLive syllabus and create sessions in a matter of minutes, or you can create your own syllabus for your group. There is also a Lectionary option, and an option for small groups of mixed ages. You'll need to register to use it, but it's free.
This section of the BRF (Bible Reading Fellowship) website has a whole host of ideas which are suitable for use in all-age worship.
This Australian site offers a wide range of music suggestions to link with the Lectionary Bible passages, including suggestions for use with children present.