No side effects have been reported from brain entrainment use.  Most producers of the technology warn against the use of brain entrainment by children under age 18, people with seizure disorders, and pregnant women.  Studies have not been conducted on these populations to date.  Additionally, (and this goes without saying) it is suggested that you do not drive while listening to brain entrainment due to the relaxing effect.
What I really like about iAwake is their standalone offerings. They produce quite a few audio pieces that are geared toward specific brainwave targets and desired results. These individual products aren't progression - based (you can listen to whatever tracks you want whenever you want), so there's no lengthy investment of your time involved. Also they're way cheaper (around $30-$50 depending on the product). In addition to manipulating brainwaves with sound, they pride themselves on their patented Biofield tech (look them up for more info).
Brainwave entrainment technology of the FUTURE – today. Brainwave entrainment using binaural beats is a thing of the past. Advanced NeuralSync™ technology uses multiple powerful sound frequencies and energetic augmentation that FORCES your brain to STOP producing defective brainwave patterns and OVERRIDES them to create positive neural feedback instead. As you continue use, your brain re-learns to produce healthy, beneficial and healing brainwaves on its own!
The fastest way to make brainwave entrainment technology work for you on your path of spiritual development is to pull back ever so slightly once you realize you have reached the peak of your nervous system’s capacity to recover from the stimulus. Because your nervous system is like a sine wave, when it is about to go into its valley, you pull back just a little bit, thereby giving your nervous system, energetic system, and hormonal system enough room to pull out all of their recovery powers. This allows you to recover from stimulus more quickly, and then you get past the waning stage and back to the waxing stage, where you can start pouring on the juice a little bit more again.
There isn’t really a one-size-fits-all track or frequency range which is right for all kids while doing homework. So that does make it difficult to recommend one thing in particular, and why I have a number of tracks for studying and focus. If they have already learnt and understood the information, but are just trying to commit it to memory for a test, then I would recommend an alpha track, like the Memorization Study Aid product I have with the 10.4Hz frequency you referred to. If they are still trying to fully understand what is being taught in a workbook, then I would recommend a track that is mainly beta frequencies, like my Study Focus tracks. In the middle, I have a number of tracks which use a combination of beta and alpha wave frequencies, like Study Booster, Study Enhancer and Cognition Enhancer. The last 3 use similar frequencies but deliver the tones and brainwave entrainment effects in different ways. As we are all wired a little differently it does sometimes take a bit of trial and error, to see what method or frequency range works best for the individual. These types of tracks are made for a general audience. In an ideal world, you would hook up to an EEG and see in real time exactly what a person responds to best, depending on the goal and current state of mind.
Brain Sync audio programs deliver pure and precisely tuned sound frequencies to the brain to drive brain activity into high level states of mind. These are brain states known as Alpha for heightened creativity and deep relaxation; Beta for high focus and concentration; Theta for meditation, insight and memory; Delta for deep sleep and healing; and Gamma to increase cognition and improve IQ.
Slower still are theta waves. Theta is best known as the brain wave state of dreaming sleep, but it is also associated with a number of other beneficial states, including increased creativity, some kinds of superlearning, increased memory abilities, visionary experiences, and what are called integrative experiences (where we make broadly-based positive changes in the way we see ourselves, others, or certain life situations).
Isochronic tones are the most recent and advanced method for brainwave entrainment audios. With isochronic tones, the same intensity is used for all tones, but they pulsate on and off at different rates. The speed, pattern, and rates of these tones can be changed and altered throughout the recording, and the brain will follow them into desired states. The use of isochronic tones opens up the ability to lead the brain into highly specific states, at specific speeds and intensities. This has opened up the doorway to producing both dominant and subdominant waves(i.e. an alpha brainwave state with subdominant theta waves), and the ability to lead the brain through different waves, at specific speeds (i.e. holding the brain in an alpha state for 10 minutes, then dropping it through theta for 20, and holding it in delta for five before bringing it back into alpha at the end of the recording.) This allows thousands of different possibilities in training the brain, and also makes the process of listening to these types of audios more natural, and more powerful. 
Alpha brainwaves are resonating just below beta brainwaves at the frequency range of 8Hz to 12Hz on an EEG. Beta brainwaves are the normal, waking life, active, rational thinking and problem solving brainwaves that are dominant in most people throughout the day. Alpha brainwaves begin to show up when relaxation occurs. Often times the simple act of closing your eyes can product spurts of alpha waves. Taking a few deep breaths or consciously relaxing will do the same. When alpha waves become dominant, the body and mind are usually comfortably relaxed.
One of the most fascinating and beneficial things about Delta brainwaves is their ability to stimulate the release of anti-aging hormones in the body, such as HGH (human growth hormone). Increased melatonin levels are also common in this state, and regular visits to Delta have also been shown to decrease cortisol levels. (Cortisol is a hormone that is released during stressful situations, that has been linked with the aging process.) In a nutshell, Delta brainwaves are very healthy, and until now have only been accessible to us during deep sleep.
Neural oscillations are rhythmic or repetitive electrochemical activity in the brain and central nervous system. Such oscillations can be characterized by their frequency, amplitude and phase. Neural tissue can generate oscillatory activity driven by mechanisms within individual neurons, as well as by interactions between them. They may also adjust frequency to synchronize with the periodic vibration of external acoustic or visual stimuli.[3]