Zearn Math vs. Monster Math - which math program for your learners?
TL;DR: Monster Math and Zearn Math both focus on CRA approach. Zearn Math uses videos to teach concepts and interactive, visual worksheets for practice - whereas Monster Math uses a game interface for both of this. Zearn Math is good for older kids who already have a strong Math foundation, whereas Monster Math is good for kids in K-3 who are looking to build a strong Math foundation.
When you want your child to really understand math concepts, apps that focus on visualising Math are much better than those that focus on just drilling. Zearn Math and Monster Math are two such math apps that take different approaches to visualising Math - so which one is better for your child?
Zearn Math
Zearn Math is a online Math program that combines short video lessons with visual and interactive problem solving interface for kids.
Some salient features of Zearn Math -
Short video lessons that explain concepts, videos have both kids and teachers.
The worksheets are designed to allow Visual and interactive problem solving

There is Math help with hints provided when kids get stuck
Monster Math
Monster Math is a fun math game that builds math fact fluency for kids. It embeds strong pedagogy and visual math solving in a really fun game. Kids think they are solving puzzles but they actually get better at Math.
Some features of Monster Math -
A full game, including fun characters, a storyline and missions and other things that keep things fun.
There are no worksheets - kids solve math in the form of solving puzzles while progressing in the game.
Hints help kids progress when they get stuck.
Strong focus on math strategies, which help kids really understand how math works, not just memorize facts.
How do these two compare against each other?
There are several similarities between Monster Math and Zearn Math - as well as some important differences.
Similarities
Both Monster Math and Zearn Math focus on helping kids understand concepts
Both have an emphasis on visualising Math and how it works
Both use the Concrete-Representational-Abstract methodology, which starts from concrete and slowly moves to abstract. Zearn Math website calls it Concrete-Pictorial-abstract - but it's the same thing.
Both products are pedagogically sound and backed by research.
Teachers love both Zearn and Monster Math.
Advantages of Zearn Math
Zearn has some important advantages.
It is full-curriculum, covers Math from grades K-8.
It includes videos with teachers explicitly explaining different concepts. This lends well to doing a flipped classroom or self-directed learning.
It has Tier-1 ESSA evidence supporting impact, which is the highest evidence possible for an educational product.
Free access to content with some restrictions.
Disadvantages of Zearn Math
The paid option is currently only available for school usage. As of this writing, there is no option for parents to sign up for a subscription. As a teacher, you'll have to mostly get the district involved to be able to use Zearn Math paid option.
The free option doesn't allow flexibility in terms of assigning any skills, or detailed report for students.
Not really fun - it's better than many worksheet only providers such as IXL, but not really designed to keep kids engaged. The videos are a one-directional medium and can struggle to hold attention of all kids.
Available only on the web - there are no mobile apps that can make it easy to use on the go.
Advantages of Monster Math
Learning and practice in the form of games. The games are inherently fun and designed to keep kids engaged and stress-free.

Focusses explicitly on Math fact fluency - and does it better than most other full-curriculum products.
Strong visual learning as kids solve puzzles within games.

Available for both school and home use. Kids can play on multiple devices - laptops, phones and tablets.
Designed to be touch-first, so kids who can't use a mouse can also use it.
Free for schools to use, reasonable price for home-usage.
Disadvantages of Monster Math
Not a full curriculum - if you are looking for something outside of Math fact fluency such as fractions or algebra, Monster Math is not right for your child.
Game-only interface means there are no videos - this can be a drawback for kids who especially prefer learning through videos.
Doesn't have ESSA Tier 1 evidence yet, so can't be purchased using ESSA funds (though it's free for schools, so this shouldn't matter).
Focusses only on grades K-3.
Which is better for your child?
This depends on what your child really needs.
If your child -
Is in a higher grade than grade 3 or 4.
Needs help with other topics such as Fractions, Geometry or Algebra
Prefers video instruction over interactive gameplay
Zearn Math might actually be better for your child.
On the other hand - if your child -
Is in Grades K-3.
Needs help with a strong Math fact fluency foundation
Loves playing video games
Doesn't like worksheets, even digital ones
Monster Math might be much better for your child.
FAQs
Is Monster Math better than Zearn Math?
As mentioned above, better can mean different things for different kids. If your child is in K-3 and loves video games - Monster Math might be better for them. If they are older, prefer video instruction and are looking for something outside of Math fact fluency - Zearn Math might be better for them.
Why is Monster Math not ESSA Tier I certified?
ESSA certifications are very expensive and Tier I certification can cost more than a million dollars. Unless it's funded by research grants, it's prohibitively expensive for small companies to fund this research themselves. Monster Math has yet to receive any research grant for research into efficacy.

