Here are some resources if you want to teach 4th grade about multiplication.
Amazing Pop-Up Multiplication Book written by Kate Perry and illustrated by Jennie Maizels– This detailed illustrated pop-up book gives students practice on different parts of the multiplication table through different events.
The Best of Times: Math Strategies that Multiply written by Greg Tang and illustrated by Harry Briggs – This approach teaches students that memorization is not the only way to prevail in multiplication. It gives students different strategies for the multiplication problems they don't know.
Hershy's Milk Chocolate Multiplication written by Jerry Pallotta and illustrated by Rob Bolster – This is a great introduction to simple multiplication problems. It shows the concept of rows, columns, and how the answer is derived.
Ten Times Better written by Richard Michelson and illustrated by Leonard Baskin – This rhyming book is a great way of illustrating the concept of multiplying by ten.
Now for My Next Number written by Margaret Park and illustrated by Sophia Esterman – This book of easy to learn and easy to sing songs will help children to practice and learn multiplication. The pictures in the book will help give students a visual of how the product is achieved.
At Multiplication.com there are a ton of kid friendly games for students to play. My favorite has to be Fleebur & Spinky. Students are trying to put together a robot dog for an alien. Students have to go to 5 different shopping centers and solve different problems to get the different parts for the robot dog.
Students will be able to find multiplication drills at MrNussbaum.com. This has multiplication facts from 1-12. Students can work on them as a timed test, dragging and dropping the answer, worksheets, or even digital flash cards.
At OnlineMathLearning.com Students can practice multiplication facts at Bee Smart Timetable. There is a multiplication fact at the bottom on two flowers and 3 bees with numbers on pots overhead. You have to click on the bee with the correct answer. It gives students 2 minutes to answer the problems.
A printable version of base ten blocks are available in case you need them. They are essential to teaching multiplication.
Students can also visualize multiplication by setting up the multiplication problem and watching it form a rectangle by incorporating the multiplication table.
Base ten paper is always helpful for students so they will be able to use to work out their multiplication problems.