http://www.highlights.com/contributor-guidelines?iCategoryID=203&CCNavIDs=3,203

Highlights for Children is a general-interest, advertising-free magazine for children up to age twelve.

Fiction - Stories for younger readers (ages three to seven) should have 500 words or fewer and should not seem babyish to older readers. Stories for older readers (ages eight to twelve) should have 800 words or fewer and should be appealing to younger readers if read aloud. Frequent needs include humor, mystery, sports, holiday, and adventure stories; retellings of traditional tales; stories with urban settings; and stories that feature world cultures. Pays $150 and up.
 
Rebus Stories - Geared toward beginning readers, should feature a variety of familiar words that can easily be shown as pictures.120 words or fewer. A surprise or twist at the end often work best. Pays $100 and up.

Verse - Purchased sparingly, is rarely longer than sixteen lines and should be meaningful for young readers. Pays $25 and up.

Nonfiction - Includes science, arts, biography, autobiography, sports, world cultures, economics, service/self-help, careers,adventure, and history. 800 words or fewer. Articles geared to younger readers (ages three to seven) are especially welcome. These should not exceed 500 words.Pays $150 and up.

Gallant Kids - 400 words or fewer. They should focus on children who are serving others through unique, interesting, kid-generated projects. Payment: $150 and up.

Puzzles, jokes, finger plays and crafts are $25 and up.

NOTE: Go here to learn their current, specific needs. http://www.highlights.com/current-needs Highlight pays well for children's stories and articles. It has a good reputation for paying. It does, however, get swamped with submissions. If you do not receive a rejection after 6-8 weeks, assume it was not accepted.