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Head-to-head · Science Learning Software

CK-12 FlexBook 2.0 vs Concord Consortium STEM Learning Tools

Updated Oct 2026
Both researched from official sources
5 checks side by side

Higher score CK-12 FlexBook 2.0 #2 in Science Learning Software 9.3/10 Free plan Free plan✓ 3 of 4 features Visit CK-12

Concord Consortium STEM Learning Tools #4 in Science Learning Software 9.1/10 Free plan Free plan✓ 4 of 4 features Visit Concord STEM

CK-12 FlexBook 2.0 leads on 0 checks, Concord Consortium STEM Learning Tools on 0, and 5 are even. Who comes out ahead on the 5 yes/no, price and count checks where we have data for both products. The editor score weighs everything else too.

Our verdict

Highest scoreCK-12 FlexBook 2.0 · 9.3/10
Free planboth
Most featuresConcord Consortium STEM Learning Tools · 4 of 4

CK-12 FlexBook 2.0 scores higher on our rubric for science learning software: 9.3 against 9.1 out of 10; our editors rank them #2 and #4.

On science scope, CK-12 FlexBook 2.0 gives you K-12 science where Concord Consortium STEM Learning Tools offers Multi-subject.

CK-12 FlexBook 2.0 is the better fit for schools wanting a fully free science platform. Concord Consortium STEM Learning Tools is the better fit for free modeling and simulation-based science learning.

CK-12 FlexBook 2.0 fits best
Schools wanting a fully free science platform
Concord Consortium STEM Learning Tools fits best
Free modeling and simulation-based science learning

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Side by side

Show only differences

Feature	CK-12 FlexBook 2.0 9.3/10 Visit ↗	Concord Consortium STEM Learning Tools 9.1/10 Visit ↗
At a glance
Editor score	9.3	9.1
Ranking	#2 in Science Learning Software	#4 in Science Learning Software
Best for	Schools wanting a fully free science platform	Free modeling and simulation-based science learning
Pricing model	Free	Free
Starting price	Free plan	Free plan
Free plan	✓	✓
Free trial	—	—
Deployment	Cloud	Cloud, Browser extension
Platforms	Web	Web
Support	Email, Community, Docs	Email, Docs
Built for	Small business, Mid-market, Enterprise	Small business, Mid-market, Enterprise
Features CK-12 FlexBook 2.0 3/4 · Concord Consortium STEM Learning Tools 4/4
Interactive simulations	✓	✓
Virtual experiments	Not checked yet	✓ (best)
Guided lessons	✓	✓
Assessment tools	✓	✓
Specs
Science scope	K-12 science	Multi-subject
Included learners	Not checked yet	Not checked yet
Supported platforms	Browser on laptop, desktop, Chromebook, tablet, or mobile device	web browser
Our review
Pros	Free customizable textbooks with videos, interactives, and practice Physics and chemistry simulations plus adaptive personalized questions Assignments, progress insights, and LMS grade passback support	Free simulations, virtual labs, and computational modeling tools Teacher classes, assignments, saved work, dashboards, and reports Multi-subject science resources with NGSS-aligned assessments
Cons	Browser-based access only Science content is focused on K–12 learning Customization and class management are teacher-led	It is a collection of tools rather than one unified SaaS product LMS embedding is available only for selected interactives Access is provided through web browsers rather than native apps
Our verdict	CK-12 FlexBook 2.0 is a browser-based science learning platform for K–12 students, teachers, parents, and schools. Its core offering combines customizable digital textbooks with interactive lessons, embedded videos, practice activities,… Read the review →	Concord Consortium STEM Learning Tools is a free collection of digital activities and software for science and STEM education. It is designed for schools, teachers, and learners working across science subjects and grade levels. Students… Read the review →

CK-12 FlexBook 2.0Science Learning Software 9.3Free plan
Concord Consortium STEM Learning ToolsScience Learning Software 9.1Free plan

Compare the top tools in

Strengths and trade-offs

CK-12 FlexBook 2.0 — where it wins
- Free customizable textbooks with videos, interactives, and practice
- Physics and chemistry simulations plus adaptive personalized questions
- Assignments, progress insights, and LMS grade passback support
Where it doesn't
- Browser-based access only
- Science content is focused on K–12 learning
- Customization and class management are teacher-led
Concord Consortium STEM Learning Tools — where it wins
- Free simulations, virtual labs, and computational modeling tools
- Teacher classes, assignments, saved work, dashboards, and reports
- Multi-subject science resources with NGSS-aligned assessments
Where it doesn't
- It is a collection of tools rather than one unified SaaS product
- LMS embedding is available only for selected interactives
- Access is provided through web browsers rather than native apps

CK-12 FlexBook 2.09.3/10 · Free plan
A broad, free science platform for schools that want customizable content and classroom tools.
Visit CK-12 Full verdict →
Concord Consortium STEM Learning Tools9.1/10 · Free plan
A free web collection for simulations, modeling, data analysis, and classroom assessment.
Visit Concord STEM Full verdict →

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Reviewed by iTechGuides Editors · Editorial team · Updated Oct 2026

Last updated 7 Oct 2026 · How we research and update