When I'm working on a Sunday School lesson or just something to teach my kids the Bible at home, I have a few free online resources that I've found helpful. I have these bookmarked so that I can find them easily.
Disclaimer: While I like these websites, I can't vouch for every piece of material on them. As always, be discerning and evaluate each thing you plan to use to make sure that it is biblically accurate.
One of the things I look for in online resources is great graphics. This is mostly because I am not a great artist and can't draw pictures that kids will enjoy. That is why I love My Wonder Studio. Some of their excellent free printables include pictures for flannelgraph stories, coloring pages, 3D pictures, and "dissected" pictures to let the kids "Be The Artist". They also have animated videos, songs, and audio adventures. The resources are navigated pretty easily by either searching or clicking on the archives on the right side (divided into age group), which takes you to an index of the tags for all of their posts.
This website is a collection of children's Bible crafts by Jesus Rolon, a children's ministry leader. There are a ton of printables for crafts, coloring pages, and activity pages. Crafts are easily found for your lesson because they are categorized (Old Testament, New Testament, VBS, holidays...). The crafts do a great job of getting to the heart of the Bible story. There is even a Spanish version of the website.
Aunties Bible Lessons has great printables for Bible crafts. Many of them have added interest (texture, moving parts, flaps, and more). There is a search box in the right column of the website to help you find what you are looking for. There is also an index for the Old Testament and the New Testament.
Amy is a super talented crafter who is kind enough to share her awesome ideas for crafts. She has an entire section for Sunday School and Bible clubs. There are ideas for working on Bible verses, crafts, and game. Some of her crafts are a little more complicated, but are awesome for older kids who need a little more of a challenge.
Kim Dailey from Sunday School Sources has a lot of games, memorizing ideas, and songs, but my favorite resource is the set of Bible character trading cards which are great for learning about the people of the Bible and where they fit into the overall timeline. There are also Books of the Bible card that would be great for memorizing the order of the books of the Bible.
This website has a lot of printable resources such as file folder games, lapbooks, and Bible verse printables. They especially have a lot of preschool and primary grade resources, but quite a bit of it could also be used with older children. I like the file folder games that help kids learn the books of the Bible and the characters of the Bible.
While Almost Unschoolers is mostly about homeschooling, there are quite a bit of Bible resources there. I especially love that there are a lot of active Bible learning, like the game where they have to categorize the books of the Bible by jumping into the correct spot drawn onto a driveway (as in the diagram above). In fact, I've used this game for lots of different Bible categories (like prophets, judges, kings, and priests...)
There are lots of printable resources at Bible Class Creations. They like to do shadow stories for telling the Bible stories and share the printables to do that. There are lots of other crafts and ideas that are tagged by the Bible character or story as well.
Sermons 4 Kids
There are a ton of free Bible lesson worksheets available at Sermons 4 Kids. If you are looking for a coloring page, word search, or multiple choice quiz, you will probably find one available on this website. They are easily found on their Old Testament and New Testament indices or you can search the website at the very top of the page. In addition, they have lots of craft and activity suggestions for each Bible lesson. The best thing is that there are a ton of Bible stories available, so if you need it you will probably find it here.
Jesus Without Language has loads of craft, game, and printable resources. The cute little Bible characters remind me of Veggie Tales characters and are made by a missionary named Kate. I love that many of the crafts are movable, since that keeps kids interested in the craft even after they are done making it. There are also little character cards that can be used in the lesson or as trading cards.
Okay... I said ten, but here's a bonus:
Bible Today 4 Kids has seven units of Bible lessons, each with 7-13 lessons. The lessons include activities, worksheets, and crafts. The worksheets can be connect-the-dots, word searches, unscrambles, fill-in-the-blanks, codes, and more.